iron sulphides at the epithermal gold-copper deposit of ...hera.ugr.es/doi/14976353.pdf · au-cu...

Iron sulphides at the epithermalgold-copper deposit of Palai-Islica (Almer|a SE Spain)

F J CARRILLO ROSUA S MORALES RUANO AND P FENOLL HACH-ALI

Department of Mineralogy and Petrology University of Granada and Instituto Andaluz de Ciencias de la Tierra(CSIC-UGR) Avda Fuentenueva sn E-18002 Granada Spain

ABSTRACT

Au-Cu mineralization at Palai-Islica occurs as disseminations in massive silicified volcanic rocks andmore abundantly in sulphide-bearing quartz veins The major ore minerals in the deposit are pyrite plusmnchalcopyrite sphalerite and galena and there is a great variety of accessory minerals including Au-Agalloys and native gold Pyrite the most abundant sulphide is closely associated with gold Sevendifferent types of pyrite have been distinguished with a variable concentration of different traceelements Among these the only one free of trace elements (type IV) is related to Au-Ag alloys Pyriteassociated with these Au-Ag alloys has cubic and pentagonal dodecahedral habits whereas pyrite withpentagonal dodecahedral habit only is from barren zones In addition there is no significant invisiblegold in the pyrite but there is a relatively large amount of Ag in collomorphic pyrite (up to 020 wt)or type III pyrite (up to 147 wt) Arsenic is the most abundant trace element in pyrite (up to611 wt) present as a metastable solid solution or as a non-stoichiometric element A variety ofmarcasite related to the gold levels also has a considerable amount of trace elements (As up to115 wt Sb up to 040 wt)

KEY WORDS pyrite gold epithermal deposit Spain

Introduction

PYRITE is the most common sulphide in theEarthrsquos crust and it forms under a wide range ofconditions (Craig et al 1998) eg in sedimen-tary metamorphic igneous and hydrothermalenvironments It reaches its greatest abundanceand is the most common mineral in hydrothermalenvironments (Ramdohr 1980) It displayssigni cant textural and morphological diversity(Murowchick and Barnes 1987) and its chemicalcomposition can also vary considerably particu-larly with respect to Co Ni and As (Rosler 1983)The Co and Ni can enter into its crystallinestructure forming a solid solution with vaesiteand catierite (Kostov and Minceva-Stefanova1981) Although As occurs in equilibrium in

minor amounts (up to 05 wt) in syntheticpyrite (Clark 1960) natural pyrite may contain asmuch as 944 wt As (Ashley et al 2000) Moreimportant is the fact that pyrite is a collector ofprecious metals such as Au and Ag (Boyle 1979Roberts 1982) as well as platinum groupelements (Rypley and Chryssoulis 1994)Therefore its chemistry has been investigated inmany deposits using diverse analytical techniques(eg Grif n et al 1991 Arehart et al 1993Morales Ruano 1994 Rypley and Chryssoulis1994 Huston et al 1995 Ashley et al 2000)Study of pyrite chemistry may also be useful inforeseeing planning and if needed minimizingthe environmental impact that can be caused byheavy-element contaminants produced byleaching of mine tailings

In the Cu-Au deposit at Palai-Islica pyrite isthe main Fe sulphide where it is closelyassociated with gold (Carrillo Rosua et al2001b 2002) The present work aims to establish

E-mail smoralesugresDOI 1011800026461036750143

Mineralogical Magazine October 2003 Vol 67(5) pp 1059ndash1080

2003 The Mineralogical Society

FIG 1 (a) Location of the main groups of volcanic rocks in the Cabo de Gata-Cartagena volcanic belt (adapted fromLopez Ruiz and Rodriguez Badiola 1980) (A) calc-alkaline volcanism (B) calc-alkaline potassic and shoshoniticvolcanism (C) ultrapotassic volcanism (D) basaltic volcanism The most important ore deposits are (1) Cabo deGata (2) Rodalquilar (3) Carboneras (Palai-Islica) (4) Herrer otilde as and Sierra Almagrera (5) Aguilas (6) Mazarron(7) Cartagena (b) Schematic geological map showing the location of the Palai-Islica deposit (adapted from IGME1974) Main geological units (1) Upper Miocene volcanic rocks of the Cabo de Gata calco-alkaline series(2) Palaeozoic-Mesozoic basement rocks belonging to the Alpujarride and Malaguide Complexes (3) Tertiarysedimentary rocks (4) Quaternary sediments (a) alluvial and (c) colluvial (5) Outcropping Palai-Islicamineralization and zone of hydrothermal alteration Faults are indicated by solid black lines (Figure slightly

modi ed from Morales et al 2000)

1060

F JCARRILLO ROSUA ETAL

possible mineralogical textural and chemicalaf nities between gold and the distinct varietiesof pyrite We focus on the textural and mineralchemistry characteristics of pyrite and otherassociated Fe sulphides (pyrrhotite and marcasite)and their crystallochemical and geochemicalimplications Pyrite also contains potentiallysigni cant amounts of trace element contaminantswhich are an important factor since the Palai-Islica deposit is located in the vicinity of the Cabode Gata Natural Park

Geological context

The main geological features of the area of thePalai-Islica deposit are well known (Arribas andTosdal 1994 Fernandez Soler 1996 Turner etal 1999) and only a summary is given here (seealso Morales Ruano et al 2000) The Palai-Islicadeposit lies within the volcanic belt of Cabo deGata-Cartagena (Fig 1a) which comprises partof the eastern end of the Internal Zone of the BeticCordilleras This Neogene volcanic belt withdifferent series of volcanic rocks (calc-alkalineshoshonitic potassic calc-alkaline ultrapotassicand basaltic series (Lopez Ruiz and RodriguezBadiola 1980)) formed within the context of asubduction zone followed by an extensionalevent (Dewey 1988 Garc otildeacutea Duenas et al1992) During the Miocene a series of magma-tism-related hydrothermal systems developedbeing controlled by a system of faults andfractures The hot uids (up to 400 ndash450ordmCMorales Ruano (1994)) reacted strongly with thehost rocks and in some districts gave rise tobroad areas of mineralization and alteration(Fig 1a) usually zoned (Fernandez Soler 1996)as in the Rodalquilar deposit where propyliticargillic advanced argillic and silicic alterationhave been observed from the outer to inner zones(Arribas et al 1995) The Palai-Islica is one ofthese areas which has become a recent target ofmineral exploration companies (Morales Ruano etal 2000) The Cu-Au epithermal mineralizationof Palai-Islica (Fig 1b) is hosted by hydrother-mally alterated calc-alkaline volcanic rocks(mainly dacites and andesites of Miocene age)related to regional strike-slip faults (N40 ndash50E)(Fernandez Soler 1996) The alteration area(propylitic sericitic argillic silici cation)consists of an oval E ndashW-striking zone 2500 mlong by 1700 m wide to which the goldmineralization is invariably related (MoralesRuano et al 2000)

Sampling and methodology

Samples were obtained from various areas ofhigh-grade gold and barren mineralization atPalai-Islica Two hundred and twenty-twopolished thin-sections of samples collected from21 drill cores were prepared to determine themineralogy and the paragenetic relationships inthis deposit

The mineralogical chemical and textural char-acteristics of Fe sulphides were determined byre ected and transmitted light microscopy scan-ning electron microscopy SEM (ZEISS DSM 950)and FESEM (LEO GEMINI) and electron micro-probe EPMA (CAMECA SX50) at the Centro deInstrumentacion Cientotilde ca of the University ofGranada Scanning electron microscopy (SEM)was used to detect As-rich zones followed bybetter-quality backscattered images using electronprobe microanalysis (EPMA) on chosen eldsX-ray mapping with EPMA identi ed zonings ofother elements (eg Co and Ni) that are not easilydetectable by SEM The operating conditions forthe X-ray mapping were 30 kV acceleratingpotential 200 nA beam current 2 mm scandistance and 300 ms X-ray peak acquisition timeper point The information obtained by electronicimages qualitative EPMA pro les was used toperform the analysis of Fe sulphides in selectedpoints of representative areas A total of 399analysis were obtained by EPMA

Natural and synthetic-certied standards wereused to calibrate the quantitative analysis Theoperating conditions were 30 kV acceleratingpotential 30 nA beam current and acquisitiontime between 60 and 300 s for X-ray peak andbackground Fifteen selected analyses of Au witha lower detection limit (475 ppm 95 con dent)were performed for pyrite (100 nA bean currentwith acquisition times of 2000 s for X-ray peakand background) The acquired X-ray intensitieswere corrected for atomic number mass absorp-tion and secondary uorescence effects using theCAMECA-PAP version of the Pouchou andPichoir (1984) procedure

Ore mineralization

The mineralization at Palai-Islica is (1) dissemi-nated in massively silici ed volcanic rockslocated exclusively in the highest part of thedeposit (2) disseminated within the ubiquitouslyhydrothermally altered rocks and (3) mostabundantly in sulphide-bearing quartz veins

EPITHERMAL IRON SULPHIDES

1061

The occurrences in veins have been describedby Morales Ruano et al (2000) and CarrilloRosua et al (2001a) for three subhorizontallevels They are characterized by Au-Ag alloysgreater mineralogical diversity enrichment in AuAg Zn Pb Cd As and Sb and uids with distinctcharacteristics (wide variation in salinity over anarrow temperature range) relative to the rest ofthe deposit

The ore minerals in the deposit (Morales Ruanoet al 1999 Carrillo Rosua et al 2001a) consistprimarily of pyrite with occasionally largechalcopyrite sphalerite and galena contentsThere is also a number of accessory mineralssuch as gold tetrahedrite-tennantite bismuthiniteAgplusmnBiplusmnPbplusmn(Cu) sulphosalts Ag and Bi tell-urides Ag sulphides and sulphosalts (achantitepolybasite-pearcite proustite-pyrargyrite stepha-nite) pyrrhotite marcasite Cu sulphides (bornitechalcocite covellite) stannite niccolite arseno-pyrite native copper and Fe-Ti-Sn oxides (rutilemagnetite hematite cassiterite)

According to Carrillo Rosua et al (2001a2002) the gold occurs as native gold (dissemi-nated exclusively in the massive silici cations)and as Au-Ag alloys in the sulphide-bearingquartz veins These alloys are relatively abundantand are always closely associated with pyriteeither included within it (Au-rich alloys) or asovergrowths (Ag-rich alloys) (Fig 2)

Mineralogical textural and chemicalcharacteristics of the Fe sulphides

Fe sulphides and in particular pyrite are by farthe most abundant sulphides in this deposit

displaying a great variety of textural and chemicaltypes There are three varieties of Fe sulphides

(1) Pyrrhotite (diameter lt100 mm) appearsincluded within porous pyrite sometimes inter-grown with chalcopyrite or magnetite Chemicalanalysis of pyrrhotite gave the formulaFe084ndash091S with very low concentrations oftrace elements (Table 1)

(2) Marcasite also occurs in minor amounts lling late microveins disseminated crystals inthe massive silci cation disseminated in thevolcanic rock of the deepest zones of thedeposit intergrown with pyrite in micro-geodesor as idiomorphic crystals in a peculiar associa-tion with pyrite and chalcopyrite as follows(Fig 3a) (a) pyrite cores sometimes with tinyinclusions of a Ag-bearing phases (b) not alwayspresent elongated chalcopyrite crystals followingthe limit between pyrite and marcasite (c) idio-morphic marcasite crystals (d) collomorphicpyrite overgrown on marcasite This mineralassociation is located at the top of Au-Ag alloybearing levels Marcasite does not show chemicalzonation as it is quite pure (Table 1) with theexception of the last textural case (Fig 3b) Thishas signi cant quantities of As (up to 115 wt)and Sb (up to 040 wt) concentrated in irregularzones in marcasite (Fig 3cd) corresponding tothe maximum concentration of Sb with theintermediate of As (Fig 4a) The increase of Asis accompanied by a decrease in the sulphurconcentration of the same order (Fig 4b) Incontrast with associated pyrite marcasite hassmall Cu and Ag contents (Fig 3fg)

(3) Pyrite is by far the most abundant phaseTwo groups of pyrite are recognized based on

FIG 2 Photomicrographs of Au-Ag alloy (a) Crystal of homogeneous Au-Ag alloy (Au) included in a non-poroustype IV pyrite (Py) (b) Crystal of Au-Ag alloy (Au) overgrowing type IV pyrite (Py)

1062


grain size ne- (lt20 mm) and medium- to coarse-grained (gt20 mm) pyrites

Tables 2 and 3 display the results of pyriteanalyses obtained by EPMA Among the traceelements As has signi cant concentrations of upto 611 wt Other elements have lower concen-trations rarely exceeding 1 wt There arenotable differences in the compositions of thetextural varieties of mediumndashcoarse and ne-grained pyrites as noted below

Table 4 presents the large acquisition-timeanalyses for Au in different types of pyrite thesealways being less than the detection limit450 ppm even in the As-rich pyrites

Medium- to coarse-grained pyrite (gt20 mm)

Generally these pyrites are disseminated in thevolcanic host rocks in zones of massive silici ca-tion and in quartz veins In the veins the pyriteaggregates may display diverse textures dissemi-nations stockwork-like veinlets brecciated crusti-form and massive aggregatesThere are three main

morphologies of idiomorphic and subidiomorphicpyrites cubic (with or without striations) penta-gonal dodecahedral and octahedral (Fig 5) Thepentagonal dodecahedralmorphology is ubiquitousthroughout the deposit the octahedral morphologyis related to near surface native gold-bearingmassively silici ed zones and the cubicmorphology occurs in the veins related to deepseated Au-Ag alloy-bearing zones

These pyrites may be differentiated into at leastfour chemical types As-bearing pyrites (type I)Co-Ni-bearing pyrites (type II) Cu-Ag bearingpyrites (type III) as well as pyrite which islacking in trace elements (type IV)

Type I As-bearing pyriteThis type of pyrite is found only within

pentagonal dodecahedral or xenomorphic crystalsin which As is enriched in cores (up to 400 mm indiameter) as well as in polygonal to irregularbands (lt20 mm in thickness)

The cores can be compact or porous (Fig 6a)and occasionally show complex irregular textures

TABLE 1 Chemistry of pyrrhotite and marcasite

A (n = 8) B (n = 31) C (n = 3)Wt Min Max Ave sd (1s) Min Max Ave sd (1s) Min Max Ave sd (1s)

Au 000 006 003 002 000 005 002 002 002 004 003 001Ag 000 003 002 001 000 005 002 001 000 002 001 001S 3787 3993 3864 065 5163 5381 5292 055 5260 5284 5271 010Sb 001 002 001 000 000 040 007 010 001 002 002 000Fe 5869 5992 5948 037 4494 4669 4598 044 4561 4633 4605 031Co 003 005 005 001 001 004 002 001 002 004 003 001Ni 000 005 001 002 000 002 000 001 000 000 000 000Cu 000 009 003 003 000 010 001 002 001 010 005 003Zn 000 002 001 001 000 018 003 003 002 004 003 001As 000 003 001 001 000 115 020 027 001 003 002 001

Total 9737 9884 9829 046 9774 10067 9929 071 987 992 989 018

AtAu 000 001 001 000 000 001 001 000 000 001 000 000Ag 000 001 001 000 000 002 001 000 000 001 000 000S 5235 5417 5302 054 6616 6696 6657 022 6639 6669 6650 013Sb 000 001 001 000 000 013 002 003 000 001 001 000Fe 4572 4753 4686 053 3294 3353 3321 017 3306 3352 3336 021Co 002 004 003 000 001 003 001 000 001 002 002 000Ni 000 004 001 001 000 001 000 000 000 000 000 000Cu 000 006 002 002 000 007 001 001 001 006 003 002Zn 000 001 001 001 000 011 002 002 001 003 002 001As 000 002 001 001 000 063 011 015 000 002 001 000

A Pyrrhotite B Idiomorphic marcasite C Non-idiomorphic marcasite n number of analyses Min minimumMax maximum Ave average sd standard deviation


1063

FIG 3 Photomicrograph (a) backscattered electron (BSE) (b) and X-ray images of As (c) Sb (d) Cu (e) and Ag (f)of the association type III pyrite (Py III) with Ag sulphide inclusions (Ag sul) chalcopyrite (Cp) idiomorphic

marcasite (Mc) and collomorphic pyrite (Py VI)

1064


(Fig 6b) in which tiny crystals of arsenopyritecan sometimes be found

Polygonal bands are scarce and occur aspentagonal dodecahedrons or cubes (Figs 6a and7a) These bands which occasionally containtennantite crystals (Fig 6a) are thin (1 ndash2 mm)with clear boundaries although they occasionallygroup together thus appearing to be thicker

Irregular bands (Fig 7b) are more commonthan the polygonal bands and are more diffuseThey show continuous variations in thicknessfrequent truncations and features typical ofdissolution or uneven growth They are normallyfound in the internal parts of the crystals rarely inthe rims

In contrast with other deposits (eg Fleet et al1989) where oscillatory As zoning affects theentire pyrite crystal the As enrichment (type Ipyrite) is restricted mainly to the most internalparts of the pyrite grains This type of pyrite canbe dissolved and overgrown by coarse pyritelacking trace elements (Fig 7b)

The chemistry of type I pyrite (Table 2) ischaracterized by a clear enrichment in As (up to338 wt) negatively correlated with S (Fig 8a)whereas no correlation exists between As and Fe(Fig 8b) In some cases there is a sporadicincrease in Cu (up to 019) particularly in thecores (Fig 6ab) Figure 8c shows that (1) the Asvalues in the cores are lower than in the bands and(2) the irregular bands are poorer in As than thepolygonal bands

Type II Co-Ni-bearing pyriteThis type of pyrite detectable only by X-ray

maps is prior to or occasionally coeval with As-bearing type I pyrite The type II pyrite(Table 2) is found in the internal parts of thepyrite crystals lacking trace elements as Co- orNi-cores or bands (Fig 7ab) This type showsthe highest Co (001 ndash069 wt) and Ni(000ndash101 wt) values and an increase inthese elements involves a slight decrease in theFe content of pyrite

000

004

008

012

016

000 020 040 060 080

As (at)

000

010

020

030

040

050

060

070

6600 6650 6700

S (at)

Sb

(at

)

As

(at

)

a b

FIG 4 (a) As vs Sb diagram showing the relationship between both elements in idiomorphic marcasite (b) S vs Asdiagram showing the inverse correlation between As and S in idiomorphic marcasite

FIG 5 SEM secondary electron images showing pyrite morphology (a) cubic habit (b) pentagonal dodecahedralhabit and (c) octahedral habit


1065

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Che

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ofm

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A(n

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(n=

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C(n

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E(n

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003

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000

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003

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000

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003

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000

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002

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000

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000

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170

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000

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200

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382

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600

282

761

280

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380

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180

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Tot

al97

78

100

0999

32

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985

110

067

996

20

5693

94

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5299

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610

063

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30

3796

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153

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000

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000

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133

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110

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120

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400

130

100

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020

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000

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020

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240

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03A

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561

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230

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151

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630

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001

840

450

640

000

050

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120

020

03

A

type

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type

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max

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sd

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viat

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mis

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of

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(lt20

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A(n

=17

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(n=

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(n=

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D(n

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d

(1s

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in

Max

A

ves

d

(1s

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Max

A

ves

d

(1s

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000

006

003

001

000

005

002

002

000

004

002

001

000

005

002

001

000

004

002

001

000

005

002

001

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000

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003

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000

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002

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000

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005

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953

23

036

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61

4550

25

530

851

85

068

496

253

79

514

51

2151

75

534

652

68

057

517

553

66

530

60

53Sb

001

003

002

001

000

002

001

001

007

046

018

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000

141

030

042

000

003

001

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000

008

002

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Fe44

53

465

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91

043

411

145

43

441

91

4441

93

461

644

50

119

416

146

29

437

31

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68

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246

27

024

452

746

33

457

30

37C

o0

010

050

020

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100

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020

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020

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040

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250

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260

190

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110

001

320

570

39Z

n0

000

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000

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000

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060

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020

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000

190

040

05A

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110

660

210

130

000

290

110

080

534

492

361

100

086

113

761

840

000

080

020

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000

120

020

03

Tot

al97

44

100

6499

50

073

899

698

76

963

32

9198

20

100

4499

37

058

980

610

056

995

30

7197

95

999

299

22

058

980

610

092

995

30

93

At

Au

000

001

001

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

Ag

000

002

001

001

000

002

001

001

000

006

003

002

000

008

002

002

000

002

001

000

000

003

001

001

S66

45

672

066

75

019

667

367

28

670

20

1865

27

666

565

88

030

647

566

93

656

20

6466

03

667

766

35

026

660

566

97

665

80

29Sb

000

001

001

000

000

001

000

000

003

015

006

003

000

049

010

014

000

001

000

000

000

003

001

001

Fe32

64

332

833

05

017

325

233

03

327

90

1831

27

332

032

46

060

311

833

08

320

10

6133

09

337

933

47

025

326

133

89

329

50

35C

o0

000

030

010

010

020

070

050

020

010

030

010

010

000

020

010

010

000

030

020

010

000

020

010

01N

i0

000

010

000

000

010

080

030

020

000

100

030

040

000

010

000

000

000

030

010

010

000

050

010

02C

u0

000

030

010

010

000

010

000

000

000

610

160

170

000

830

130

180

010

250

080

070

000

830

360

25Z

n0

000

020

010

010

000

020

010

010

000

110

040

030

000

060

010

010

000

040

010

010

000

120

020

03A

s0

060

350

120

070

000

160

060

050

292

501

290

610

043

362

061

020

000

050

010

010

000

070

010

02

A

type

V(f

ram

boid

sse

nsu

stri

cto)

B

ty

peV

(pse

udof

ram

boid

s)

C

type

VI

(col

lom

orph

icpo

rous

pyri

te)

Dt

ype

VI

(bro

wn

collo

mor

phic

pyri

te)

E

type

VII

(mic

ro-g

eode

s)

Fty

peV

II(p

yrit

ein

terg

row

ths

inch

alco

pyri

te)

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion

Type III pyrite with Cu and Ag

Associated with idiomorphic marcasite in theabove-described marcasite there are pyrites(Table 2) which have signi cant amounts of Cu(up to 062 wt) and Ag (up to 147 wt)

Figure 3e and f shows extended enrichments ofCu and minor in Ag throughout all pyrite grainswhereas in Fig 9 we observed that the Cu and Aglevels are approximately equal with a lsquoback-groundrsquo of Cu of 010 at

FIG 6 (a) BSE and X-ray images of As-rich type I pyrite overgrown by nearly stoichiometric pyrite type IV (1) coreof type I pyrite with porous character (dark areas) (2) thin polygonal bands of type I pyrite with a tennantite (Ten)inclusion On the right hand side of the gure note the As Cu and Sb X-ray images where Cu and Sb are slightlyenriched in the type I pyrite core (b) BSE and X-ray images of As-rich type I pyrite core with a complex texture anda tiny arsenopyrite inclusion (Apy) On the right hand side of the gure note the As and Cu X-ray images from the

marked area

1068


Type IV pyrite lackingtrace elementsThis type of pyrite volumetrically the most

abundant is characterized by neglible concentra-tions of trace elements (Table 2) Type IV pyrite is

found as disseminations throughout the volcanichost rock or in quartz veins and silici ed zoneswhere it can contain types I and II pyrites or elseappear as homogeneous crystals Type IV pyrite

FIG 7 (a) BSE and X-ray images of type I (As-bearing) and type II (Co-Ni-bearing) pyrite hosted by type IV pyrite(1) polygonal bands of type I pyrite with a pentagonal dodecahedral morphology overgrown by (2) a polygonal bandwith cubic morphology As Co and Ni X-ray images on the right hand side of the gure reveal Co-Ni bearing typeII pyrite in core and bands (3) (b) BSE and X-ray images of type I (As-bearing) and type II (Co-Ni-bearing) pyritehosted by type IV pyrite (1) irregular bands of type I with abundant truncations in the inner part of the crystal(2) irregular bands of type I in the rim of the crystal On the right hand side of the gure note the As Co and Ni

X-ray images with the non-coincident Co-rich and Ni-rich pyrite (3)


1069

frequently has pore-rich zones that generallycoincide with the central parts of the crystalswhich also have high concentrations of mineralmicroinclusions especially pyrrhotite chalco-pyrite rutile and magnetite

It should be noted that Au-Ag alloys are hostedby the type IV pyrite preferentially included inthe pore-free zones (Fig 2a)

Fine-grained pyrites (lt20 mm)

This group comprises framboidal (type V) andcollomorphic (type VI) pyrites as well as micro-

geodes and intergrowths of pyrite in chalcopyrite(type VII)

Type V framboidal pyriteThis type is relatively rare and occurs in two

varieties (1) As framboids sensu stricto(Fig 10a) generally spherical and lt50 mm insize The pyrite microcrystals very closelypacked are subidiomorphic and equigranular(plusmn2 mm) In some cases the framboidal pyrite isovergrown by coarse-grained type IV pyrite(2) As lsquopseudoframboidsrsquo (Fig 10b) that areloosely packed or even disaggregated with sizes

00

05

10

15

20

25

30

6 4 5 65 0 6 55 6 6 0 6 6 5 6 7 0 S (at)

Type I

Type VI

00

05

10

15

20

25

30

31 0 31 5 32 0 32 5 33 0 33 5 Fe (at)

0

2

4

6

8

10

12

14

0 02 04 06 08 1 12 14 As (at)

Type I (ii)

(iii)

(i)

As

(at

)Fr

eque

ncy

As

(at

)

Type I

Type VI

a

b

c

FIG 8 (a) S vs As diagram showing inverse correlation with different slopes for type I and type VI pyrite (b) Fe vsAs diagram showing no correlation in type I pyrite but good inverse correlation in type VI pyrite (c) Arseniccontent frequency histogram in type I pyrite (i) cores (ii) polygonal bands (iii) irregular bands Observe that the

cores have the lowest As content while the highest As values are in the polygonal bands

1070


of up to 50 mm In contrast to the framboids sensustricto the pyrite microcrystals here are roundedor oval-shaped and vary in size from lt1 to 5 mmThe outermost crystals are the largest

Both types of framboidal pyrites show smallamounts of trace elements As being the mostabundant (average of 018 wt Table 3)

Type VI collomorphic pyriteThese pyrites occur principally in two genera-

tions of overgrowth on previous pyrite crystalsalthough they can also overgrow idiomorphicmarcasite and exceptionally chalcopyrite TypeVI occurs as either porous collomorphic pyrite(Fig 10c) or as brown collomorphic pyrite underre ected light microscope (Fig 10d)

These pyrites have the largest amounts of As(008ndash611 wt) Cu (000ndash126 wt) Sb(000ndash141 wt) and Ag (000 ndash020 wt)but the smallest Fe contents (419ndash462 wt)of all the pyrites analysed in the deposit Nickeland Zn have also been detected (Table 3) Arsenicis negatively correlated with S with a slope( ndash158) more pronounced than for the type Ipyrite (Fig 8a) The As is also negativelycorrelated with Fe (Fig 8b)

000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)

FIG 9 (a) Cu vs Ag diagram showing two types ofbehaviour (represented by ellipses) of the relation

between both elements in type III pyrite

FIG 10 Photomicrographs of type V and type VI pyrite (a) Framboids sensu stricto closely packed withsubidiomorphic coalescing microcrystals (b) lsquoPseudoframboidrsquo of loosely packed pyrite of rounded or oval shapes(c) Porous collomorphic pyrite (1) overgrowing marcasite and coarse pyrite (2) (d) Bands of brown collomorphic

pyrite showing graded shading (1) overgrowing coarse pyrite (2)


1071

Within the overgrowths of collomorphic pyritethe rst generation is usually richer in As than thesecond one (Fig 11ab) with some chemicaldifferences between the two textural varieties

The porous collomorphic pyrite contains lessAs (053ndash449 wt) than the brown collo-morphic pyrite It also has relatively largeamounts of Ag Cu Ni and Zn and these aredirectly correlated with As concentration

(Fig 12) a feature that is evident from theX-ray maps in Fig 10a for Cu Ag and Ni

The brown collomorphic pyrite has the highestAs content (008ndash611 wt) It is is alsoenriched in Ag Cu and Sb but not in Zn or NiIn contrast with the porous variety there is nodirect correlation between these elements and As(Fig 12) However at high As concentrationsthere is an enrichment in Ag Cu and Sb and the

FIG 11 (a) BSE and X-ray images of type VI pyrite There are two bands (1) and (2) of collomorphic pyriteovergrowing marcasite (Mc) with the former being richer in Cu Ag As and Ni than the latter (b) BSE and X-rayimages of type VI pyrite Collomorphic pyrite (1) overgrowing coarse type IV pyrite (2) The As concentration isrelatively homogeneous in this collomorphic pyrite just the opposite of the Cu and Sb concentrations which are

enriched in the ner bands

1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)

FIG 12 Binary diagrams showing variations between different elements in type VI pyrite (a) porous collomorphicpyrite and (b) brown collomorphic pyrite


1073

nature of Cu and Sb distributed in As-rich bandsis shown in the X-ray maps in Fig 11b

Type VII pyrite micro-geodes and intergrowths inchalcopyrite

In both cases (Fig 13) pyrite occurs aschemically homogeneous xenomorphic ne-grained (lt15 mm) aggregates located in chalco-pyrite crystals The micro-geodes tend to be up to400 mm in diameter and sometimes host marcasitecrystals The pyrite intergrowths are distributedalong elongated zones within the chalcopyrite

The trace-element concentration is quite low inboth cases similar to that of the coarse-grainedpyrite of type IV

Based on the textural evidence summarizedabove we propose a paragenetic sequence for thedistinct types of Fe-sulphides at veins presentedin Fig 14

Genetic considerations

Origin of pyriteThe pyrite of the Palai-Islica deposit originatedfrom hydrothermal uids However the formationpathways of pyrite from hydrothermal uids arecontroversial and an intermediate precursor isthought to be necessary (eg Benning et al2000) Moreover certain textural characteristicsobserved in the pyrite of this deposit (eg relics ofpyrrhotite presence of framboids) should beconsidered in evaluating possible processes ofpyrite formation such as (1) the transformationofpyrrhotite and marcasite and (2) the formation ofpyrite framboids

The transformation of pyrrhotite and marcasite

Some of the pyrite in this deposit may initiallyhave crystallized as pyrrhotite proper andsubsequently been transformed into pyrite byone of the mechanisms proposed by Fleet (1978)and by Murowchick and Barnes (1986) Due tothe smaller molar volume of pyrite thistransformation could account for the existenceof the high-porosity zones particularly in thepyrite lsquolackingrsquo trace elements Marcasite hadalso been a precursor of type VII pyrite as shownby the textural evidence

The formation of framboids

Occasionally the precursor of the medium- tocoarse-grained pyrite may have been framboidal

pyrite which in turn may have had greigite as aprecursor (Wilkin and Barnes 1997) Thepresence of zones in the porous type IV pyritewould correspond to zones where the recrystalli-zation was incomplete whereas the abundantmicro-inclusions in the porous pyrite could beinterpreted as crystals that were trapped in theframboidal spaces According to Wilkin andBarnes (1997) the maximum temperature atwhich framboidal pyrite may nucleate is 225ordmCThis temperature is consistent with the lowerrange of temperatures determined by microther-mometry of uid inclusions (between 120 and465ordmC) in quartz associated with pyrite (MoralesRuano et al 2000)

Evolution of As contents in the pyrite

Pyrites in other hydrothermal deposits havecharacteristic oscillatory banding due to varia-tions in a relatively continuous supply of Asduring precipitation (eg Fleet et al 1989)However the As supply to the Palai-Islicapyrites seems to have been more episodicconcentrated in the mineralization areas espe-cially in relation to gold-bearing levels but not inthe hydrothermal alteration Based on textural andmineral chemistry data there have been two mainepisodes of well-de ned As enrichment

The rst As-rich episode associated with theinitial stages of formation of the depositproduced the As-rich cores and bands of type Ipyrite with some related tiny crystals ofarsenopyrite (main stage of pyrite precipitation)It was occasionally accompanied by the incor-poration of Cu which is sometimes linked to theformation of the tennantite inclusions The As-rich cores and bands are the product ofcontinuous pyrite growth as indicated by theconcentric nature of the banding the coherencebetween the morphology of the banding and thecrystal habits

Following this rst As-rich episode there was astage of As-free pyrite crystallization (type IV)The type IV pyrite is not only volumetricallysigni cant in places forming massive aggregatesbut it also hosts gold alloys

The second As-rich episode associated withthe nal stages of the Fe sulphide deposition ischaracterized by the presence of idiomorphicmarcasite and two varieties of collomorphicpyrite(type VI) the most As-rich pyrites of Palai-IslicaTwo consecutive bands can be distinguishedwiththe rst one mainly richer in As

1074


Accordingly the As entered into the pyritestructure in two stages and appears to beincorporated by two different mechanisms assuggested by the relationship between As S andFe (1) in pyrites from the rst episode the Ascontent of the pyrite is negatively correlated withS while the Fe content is constant (Fig 7ab) TheAs was incorporated in a metastable solid solutionin the S positions It could be related to layers oflsquomarcasite-likersquo structure with high As content

(Fleet et al 1989 Simon et al 1999) or else asclusters with a lower As content in the pyritestructure (Savage et al 2000) (2) In contrast inpyrites produced during the second episode the Asis negatively correlated with both the S and the Fe(Fig 7ab) and the increase in the As concentra-tion is accompanied by increasing contents of CuAg Sb Zn and Ni In this case there are nocrystallochemical studies on the entrance of Asinto pyrite associated with decreasing S and Fe

PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV

Cores of pyritewith As (type I)

Pyrite type II

Polygonal bands ofpyrite with As (type I)

Irregular bands ofpyrite with As (type I)

Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation

Marcasite microveins

Idiomorphic marcasiteassociated with type III pyrite

FIG 14 Paragenetic sequence of the different types of Fe-sulphides showing their relationship with the gold at Palai-Islica mineralization

FIG 13 Photomicrographs of type VII pyrite (a) Micro-geodes of pyrite (py) in chalcopyrite (cp) (b) Bands ofmicrocrystals of pyrite (py) in coarse-grained chalcopyrite (cp)


1075

contents However this correlation might beexplained by either the entrance of cationic Asandor non-stoichiometric As (Fleet and Mumin1997) Although the presence of collomorphictextures does not necessarily imply colloidalorigin (Roedder 1968) colloidal precipitation isnonetheless an attractive hypothesis to explain theparticular textural and chemical characteristics ofthe collomorphic pyrite overgrowths sincecolloidal particles might be quite effective intrapping As ions Colloidal particles with an Ascovering (negatively charged) could in turn act aslsquotrapsrsquo for cations This mechanism could explainthe relatively large amounts of Cu Ag Sb Zn andNi as well as the Fe de cit found in thecollomorphic pyrite overgrowths

Type III pyrite-chalcopyrite-marcasite association

The mineral association of type III pyrite-chalcopyrite-marcasite could be related to theformation of Au-Ag alloy horizons because of itslocation at the top of the horizons The low d34Ssignature of these sulphides different from therest of the deposit (author data) could be causedby another kind of uid implicated in the mixingprocesses mentioned by Morales Ruano et al(2000)

The high Ag and Cu contents of type III pyriteand of As and Sb in marcasite are notable We caninfer from Fig 9 two paths for the entry of Cuinto pyrite (1) below 010 at Cu (with whichthere is no concomitant increase in Ag) It iswidely spread through the pyrite crystals (Fig 3)(2) Above 010 at Cu the increase in Cu is in a11 relationship with Ag These high concentra-tions of Cu and Ag not are due to the presence ofmicroscopic inclusions as optical study shows sothey must be produced by (a) very abundantsubmicroscopic inclusions of chalcopyrite andorCu-Ag phases always intergrown with chalco-pyrite and (b) a true solid solution of Cu and Ag

The entry of As in marcasite is the same as fortype I pyrite due to the 11 correlation betweenAs and S In addition a small amount of Sb entersthe marcasite when the concentration of As isgt010 at It seems that the maximum Sb occursat ~020 at of As

We explain the chalcopyrite dispositionbetween marcasite and pyrite as the result of adiffusion process in which Cu migrates to thelimit between pyrite and marcasite This processalso liberates Ag to form Ag mineral inclusions(Ag suphides and sulphosalts)

Relationshipsbetween pyrite habit and gold crystalsWe have found a close relationship between thepyrite habit and the presence of gold crystalsSpeci cally the gold is found on the mineralizedlevels containing type IV pyrite displaying a greatvariety of crystallographic habits (cubes andpentagonal dodecahedrons or octahedrons andpentagonal dodecahedrons) In contrast barrenzones occur where only the pentagonal dodecahe-dral morphology is developed

Correlations between pyrite morphology andmetal-enriched zones has also been described inother deposits (eg Sunagawa 1957 Bush et al1960 Amstutz 1963) Pyrite morphology isdetermined by crystalline growth mechanisms(primarily screw dislocation and layer-by-layer)which are dependent on the temperature anddegree of supersa turat ion of the uid(Murowchick and Barnes 1987) Pyrite deposi-tion in the Au-mineralized zones in Palai-Islicamay have been associated with a change in thedegree of supersaturation of the mineralizing uid possibly due to mixing of uids suggestedby the uid inclusion data reported by MoralesRuano et al (2000)

Au and Ag contents in pyrite

The Au contents obtained by EPMA for thedifferent pyrite types are uniformly low (Tables 2and 3) Selected high-acquisition-time analysis ofdifferent pyrite types (Table 4) also present lowAu contents never greater than the detection limitof 475 ppm even in the As-rich pyrites which areconsidered to be potentially invisible-gold-bearing (eg Cook and Chryssoulis 1990)These results in addition to the abundance ofvisible gold grains suggest that invisible goldmay not be volumetrically signi cant in theoverall deposit (Carrillo Rosua et al 2002) asin other deposits where Au in pyrite reaches morethan 1000 ppm (eg Mao 1991 Fleet et al 1993Asadi et al 1999 Simon et al 1999)

The relatively large values of Ag found in thetype III pyrite (up to 147 wt) and in the typeVI collomorphic pyrite (up to 02 wt) areworthy of note This Ag concentration is one ofthe highest found in pyrite to date (Larocque etal 1995 up to 1426 ppm Grif n et al 1991 upto 625 ppm Tompkins et al 1997 up to200 ppm Roberts 1982 up to 300 ppm Ashleyet al 2000 up to 88 ppm) In our case the supplyof Ag by the pyrite to the deposit as a whole couldbe noteworthy especially in the super cial zones

1076


of the deposit where there are no other Ag-bearing phases apart from type VI pyrite

Implications for the formation conditions of the presenceof marcasite

According to Murowchick and Barnes (1986) ifmarcasite crystallizes directly from a hydro-thermal uid which is the case for the Palai-Islica deposit then the pH must be lt5 Thereforelow pH at least is expected at several pointslarge-scale silici cation hydrothermal alterationin the deepest part of the deposit the formation ofpyrite micro-geodes and the formation ofidiomorphic marcasite (related to the Au-Agalloy levels)

Conclusions

(1) In this study we have noted the greatusefulness of backscattered electron imagesobtained by SEM to determine heterogeneitiesin compositions in pyrites appearing homoge-neous under re ected light It is neverthelessnecessary to use X-ray mapping with EPMA sinceSEM cannot detect anomalies of elements that donot have high atomic weights commonly presentin pyrites in hydrothermal deposits (Co and Ni)Therefore EPMA is worthwhile despite being

less versatile and more time-consuming (~90 minto obtain values for four elements)

(2) Most of the pyrite formed directly from thehydrothermal uid although pyrrhotite andframboidal pyrite may also have acted to alesser extent as precursors to pyrite during the rst stages of crystallization

(3) Among the trace elements in pyrite As isthe most abundant with signi cant Co and NiThese elements are distributed in bands and coresof medium- to coarse-grained pyrite crystalsindicating that they were incorporated in thepyrite structure during the early stages of pyritecrystallizationArsenic and to a lesser degree NiAg and Cu can also be concentrated in the latestages of pyrite crystallization (as collomorphicpyrite)

It is probable that As enters the pyrite structurein two ways (1) as a metastable solid solution(inverse correlation of As with S) with nosigni cant entry of other elements or (2) as anon-stoichiometricelement by colloidal precipita-tion (inverse correlation of As vs S and of As vsFe) The latter is associated with the entry of othertrace elements such as Cu Sb Ag and Ni Cobaltand Ni substitute for Fe in the pyrite structure

Marcasite also has signi cant amounts of As(with a crystallochemical behaviour similar totype I pyrite) and to a smaller extent of Sb This

TABLE 4 Large-acquisition-time microprobe analyses for Au in different types of pyrite (wt)

Pyrite type S Fe As Co Ni Total Au (ppm)

I 5196 4570 010 016 018 9809 10I-II 4893 4420 278 024 008 9622 120I-II 5016 4489 249 033 007 9795 50I-II 5196 4586 059 010 009 9859 160II-I 5097 4406 070 066 041 9679 30II-I 5113 4476 089 046 031 9754 70IV 5159 4531 002 007 000 9700 120IV 5216 4575 003 007 000 9801 140IV 5238 4608 001 006 000 9853 0IV 5219 4593 017 007 002 9837 120

VI-B 4888 4268 486 006 000 9648 30VI-B 4940 4210 572 006 000 9727 30VI-B 4770 4104 542 005 000 9421 140VI-B 4922 4287 545 006 000 9760 130VI-B 4951 4223 555 006 000 9734 60

Minimum 4770 4104 001 005 000 9421 0Maximum 5238 4608 572 066 041 9859 160Average 5054 4423 232 017 008 9733 81

St dev (1s) 151 165 241 018 013 113 54


1077

phase together type III pyrite may have under-gone a diffusion process

(4) The medium- to coarse-grained pyritelacking trace elements (type IV) is the only hostto Au-Ag alloys These alloys together with thenative gold are the main gold-bearing phasesThe so-called invisible gold in the pyrite is ofminor importance However the pyrite occasion-ally contains signi cant amounts of Ag in sometextural varieties (eg types III and VI pyrite)

(5) Since the gold is closely associated with thepyrite its extraction would necessarily involvelarge volumes of pyrite with high concentrationsof heavy metals (As Co and Ni) all highlycontaminatingGiven the proximity of the depositto the Cabo de Gata Natural Park the mining ofthis deposit would require special measures tominimize the environmental impact

Acknowledgements

The authors thank Serrata Resources SA for thehelp they have provided during this investigationThis research has also been supported by theprojects No PB-97-1211 BTE2001-3308 andRNM-0131 Research Group of the Junta deAndalucotilde a We thank Dr Peter Poltz (FELMI-ZFE Graz University of Technology) for his helpwith FESEM study of pyrite and Prof C Laurinfor correcting the English

References

Amstutz GC (1963) Accessories on pyrite pyritezon ing and zoned pyri te SchweizerischeMineralogische und Petrographische Mittteilungen 33 111 ndash122

Arehart GB Chyssoulis SL and Kesler SE (1993)Gold and arsenic in iron sul des from sediment-hosted disseminated gold deposits implications fordepositional processes Economic Geology 88171 ndash185

Arribas A and Tosdal R (1994) Isotopic compositionof Pb in ore-deposits of the Betic Cordillera SpainOrigin and relationship to other European depositsEconomic Geology 89 1074 ndash1093

Arribas A Cunningham CG Rytuba JJ Rye ROKelly WC Podwysocki MH McKee EH andTosdal RM (1995) Geology geochronology uidinclusions and isotope geochemi stry of theRodalquilar gold alunite deposit Spain EconomicGeology 90 795 ndash822

Asadi HH Voncken JHL and Hale M (1999)Invisible gold at Zarshuran Iran Economic Geology94 1367 ndash1374

Ashley PM Creagh CJ and Ryan CG (2000)Invisible gold in ore and minerals concentrates fromthe Hillgrove gold-antimony deposits NSWAustralia Mineralium Deposita 35 285 ndash301

Benning LG Wilkin RT and Barnes HL (2000)Reaction pathways in the Fe-S system below 100ordmCChemical Geology 167 25 ndash51

Boyle RW (1979) The geochemistry of gold and itsdeposits Geological Survey of Canada Bulletin 280

Bush JB Cook DR Lovering TS and Morris HT(1960) The Chief Oxide-Buring area discoveriesEast Tintic district Utah A case history ndash Part 1USGS studies and explorat ion EconomicGeology 55 1116 ndash1147

Carrillo Rosua FJ Morales Ruano S and FenollHach-Al otildeacute P (2001a) Mineralogy and mineralchemistry of precious metals of the Cu-Au miner-alisation at the Palai-Islica deposit Almer otilde a SESpain Pp 715 ndash718 in Mineral Deposits at theBegining of the 21st Century (A Piestrzynski et aleditors) Balkema Lisse The Netherlands

Carrillo Rosua FJ Morales Ruano S and FenollHach-Al otilde P (2001b) Tipolog otildeacutea de la pirita en eldeposito epitermal de Palai-Islica (CarbonerasAlmer otildeacutea) Implicaciones en la genesis del oroBoletgn de la Sociedad Espanola de Mineralog ga24-A 151 ndash152

Carrillo Rosua FJ Morales Ruano S and FenollHach-Al otilde P (2002) The three generations of gold inthe Palai-Islica epithermal deposit SoutheasternSpain The Canadian Mineralogist 40 1465 ndash1481

Clark LA (1960) The Fe-As-S system Phase relationsand applicat ions Economic Geology 55 1345 ndash1381

Cook NJ and Chryssoulis SL (1990) Concentrationsof lsquoinvisible goldrsquo in the common sulphides TheCanadian Mineralogist 28 1 ndash16

Craig JR Vokes FM and Solberg TN (1998)Pyrite physical and chemical textures MineraliumDeposita 34 82 ndash101

Dewey JF (1988) Extensional collapse of orogensTectonics 7 1123 ndash1140

Fernandez Soler JM (1996) El vulcanismo calco-alcalino en el Parque Natural de Cabo de Gata-Nijar (Almeria) Estudio volcanologico y petrologi-co PhD thesis Universidad de Granada SociedadAlmeriense Historia Natural 295 pp

Fleet ME (1978) The pyrrhotite-marcasite transforma-tion The Canadian Mineralogist 16 31 ndash35

Fleet ME and Mumin AH (1997) Gold-bearingarsenian pyrite and marcasite and arsenopyrite fromCarlin Trend gold deposits and laboratory synthesisAmerican Mineralogist 82 182 ndash193

Fleet ME McLean PJ and Barbier J (1989)Oscillatory-zoned As-bearing pyrite from strata-bound and stratiform gold deposits An indicator or

1078


ore uid evolution Pp 356 ndash362 in The Geology ofGold Deposits The Perspective in 1988 (RRKeays WRH Ramsay and DI Groves editors)Economic Geology Monograph 6 EconomicGeology Publishing Company El Paso Texas

Fleet ME Chryssoulis SL MacLean PJ DavidsonR and Weisener CG (1993) Arsenian pyrite fromgold deposits Au and As distribution investigated bySIMS and EMP and colour staining and surfaceoxidation by XPS and LIMS The CanadianMineralogist 31 1 ndash17

Garc otilde a Duenas V Balanya JC and Mart otilde nezMart otilde nez JM (1992) Miocene extensional detach-ments in the outcropping basements of the northernAlboran Basin (Betics) Geomarine Letters 1288 ndash95

Grif n WL Ashley PM Ryan SG Sie SH andSuter GF (1991) Pyrite geochemistry in the NorthArm epithermal Ag-Au deposit QueenslandAustral ia A proton -microprobe study TheCanadian Mineralogist 29 185 ndash198

Huston DL Sie SH Suter GF Cooke DR andBoth RA (1995) Trace elements in sul de mineralsfrom eastern Australian volcanic hosted massivesul de deposits Part I Proton microprobe analysesof pyrite chalcopyrite sphalerite and Part IISelenium levels in pyrite comparison with d34Svalues and implications for the source of sulfur involcanogenic hydrothermal systems EconomicGeology 90 1167 ndash1196

IGME (Instituto Geologico y Minero de Espana) (1974)Mapa Geologico de Espana Escala 150000 Hoja1046 (24 ndash42) Sorbas Servicio de publicacionesMinisterio de Industria

Kostov I and Minceva-Stefanova J (1981) SulphideMinerals Crystal Chemistry Paragenesis andSystematics Bulgarian Academy of Sciences 212pp

Larocque ACL Jackman JA Cabri LJ andHodgson CJ (1995) Calibration of the ion micro-probe for the determination of silver in pyrite andchalcopyrite from the Mobrun VMS deposit Rouyn-Noranada Quebec The Canadian Mineralogist 33361 ndash372

Lopez Ruiz J and Rodriguez Badiola E (1980) Laregion volcanica del sureste de Espana EstudiosGeologicos 36 5 ndash63

Mao SE (1991) Occurrence and distribution ofinvisible gold in a Carlin-type gold deposit inChina American Mineralogist 76 1964 ndash1972

Morales Ruano S (1994) Mineralog ga geoqu gmica ymetalogenia de los yacimientos hidrotermales del SEde Espana PhD thesis Universidad de GranadaSpain 254 pp

Morales Ruano S Carrillo Rosua FJ Fenoll-Hach-Alotilde P de la Fuente Chacon F and Contreras

Lopez E (1999) The Au-Cu epithermal deposit atPalai-Islica deposit (Almeria Southeastern Spain)Preliminary data Pp 59 ndash62 in Mineral DepositsProcesses to Processing (CJ Stanley et al editors)Balkema Rotterdam The Netherlands

Morales Ruano S Carrillo Rosua FJ Fenoll-Hach-Al otilde P de la Fuente Chacon F and ContrerasLopez E (2000) Epithermal Cu-Au mineralisationin the Palai-Islica deposit Almerotildeacutea SoutheasternSpain uid inclusion evidence of mixing of uids asa guide to gold mineralisation The CanadianMineralogist 38 553 ndash566

Murowchick JB and Barnes HL (1986) Marcasiteprecip itat ion from hydrothermal solut ionsGeochimica et Cosmochimica Acta 50 2615 ndash2629

Murowchick JB and Barnes HL (1987) Effects oftemperature and degree of supersaturation on pyritemorphology American Mineralogist 72 1241 ndash1250

Pouchou JL and Pichoir F (1984) Un nouveau modelede calcul pour la microanalyse quantitative perspectrometr ie de rayons X La ResercheAerospatiale 3 167 ndash192

Ramdohr P (1980) The Ore Minerals and theirIntergrowths Pergamon Press Oxford UK 1202 pp

Roberts FI (1982) Trace element chemistry of pyrite auseful guide to the occurrence of sulphide base metalmineralisation Journal of Geochemical Exploration 17 49 ndash62

Roedder E (1968) The noncolloid al origin oflsquocoll omorphic rsquo textures in sphaleri te oresEconomic Geology 63 451 ndash471

Rosler HJ (1983) Lehrbuch der Mineralogie VEBDeutscher Verlag fur Grundstof ndustrie LeipzigGermany 886 pp

Rypley EM and Chryssoulis SL (1994) Ion micro-probe analysis of platinum-group elements insulphide and arsenide minerals from the BabbittCu-Ni deposi t Duljth complex Minnesot aEconomic Geology 89 201 ndash210

Savage KS Tingle TN OrsquoDay PA WaychunasGA and Bird DK (2000) Arsenic speciation inpyrite and secondary weathering phases MotherLode Gold District Tuolumne County CaliforniaApplied Geochemistry 15 1219 ndash1244

Simon G Huang H Penner-Hahn JE Kesler SEand Kao LH (1999) Oxidation state of gold andarsenic in gold-bearing arsenian pyrite AmericanMineralogist 84 1071 ndash1079

Sunagawa I (1957) Variation in the crystal habit ofpyrite Geological Survey of Japan Report 1751 ndash47

Tompkins LA Groves DI Windrim DP JablonskiW and Grif n WL (1997) Petrology mineralchemistry and signi cance of Fe-sulphides from themetal dispersion halo surrounding the Cadjebut Zn-


1079

Pb MTV deposit Western Australia AppliedGeochemistry 12 37 ndash54

Turner SP Platt JP George RMM Kelley SPPearson DG and Nowell GM (1999) Magmatismassociated with orogenic collapse of the Betic-Alboran domain SE Spain Journal of Petrology 40 1011 ndash1036

Wilkin RT and Barnes HL (1997) Formation

processes of framboidal pyrite Geochimica et

Cosmochimica Acta 61 323 ndash339

[Manuscript received 25 April 2002revised 16 June 2003]

1080


FIG 1 (a) Location of the main groups of volcanic rocks in the Cabo de Gata-Cartagena volcanic belt (adapted fromLopez Ruiz and Rodriguez Badiola 1980) (A) calc-alkaline volcanism (B) calc-alkaline potassic and shoshoniticvolcanism (C) ultrapotassic volcanism (D) basaltic volcanism The most important ore deposits are (1) Cabo deGata (2) Rodalquilar (3) Carboneras (Palai-Islica) (4) Herrer otilde as and Sierra Almagrera (5) Aguilas (6) Mazarron(7) Cartagena (b) Schematic geological map showing the location of the Palai-Islica deposit (adapted from IGME1974) Main geological units (1) Upper Miocene volcanic rocks of the Cabo de Gata calco-alkaline series(2) Palaeozoic-Mesozoic basement rocks belonging to the Alpujarride and Malaguide Complexes (3) Tertiarysedimentary rocks (4) Quaternary sediments (a) alluvial and (c) colluvial (5) Outcropping Palai-Islicamineralization and zone of hydrothermal alteration Faults are indicated by solid black lines (Figure slightly

modi ed from Morales et al 2000)

1060



Geological context






Ore mineralization



1061











1062















Total 9737 9884 9829 046 9774 10067 9929 071 987 992 989 018




1063



1064









000

004

008

012

016

000 020 040 060 080

As (at)

000

010

020

030

040

050

060

070

6600 6650 6700

S (at)

Sb

(at

)

As

(at

)

a b




1065

TA

BL

E2

Che

mis

try

ofm

ediu

m-

toco

arse

-gra

ined

pyri

te(gt

20m m

)

A(n

=19

)B

(n=

21)

C(n

=39

)D

(n=

37)

E(n

=18

)F

(n=

107)

Wt

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Au

000

016

003

004

000

006

003

002

000

016

003

003

000

005

002

001

000

005

002

001

000

010

002

002

Ag

000

006

001

001

000

003

001

001

000

009

002

002

000

005

001

001

000

147

018

035

000

017

002

002

S51

31

530

352

16

043

505

052

62

515

90

6449

39

536

152

10

078

508

753

83

527

20

7952

07

535

352

79

044

515

554

85

533

00

54Sb

000

003

001

001

000

011

002

002

000

019

003

004

000

004

001

001

000

004

001

001

000

006

001

001

Fe45

38

465

646

10

032

443

946

06

453

30

5344

51

467

546

05

049

443

946

41

456

60

6044

42

465

245

78

052

446

846

98

461

90

43C

o0

000

090

030

020

020

510

170

160

000

070

020

010

010

690

250

190

010

030

020

010

000

120

030

02N

i0

000

030

000

010

000

900

170

270

000

050

010

010

001

010

210

260

000

010

000

000

000

080

010

01C

u0

000

190

020

040

000

160

020

030

000

140

020

030

000

080

010

020

010

620

200

160

000

700

040

11Z

n0

000

300

030

070

000

020

010

010

000

040

010

010

000

040

010

010

000

040

010

010

000

390

020

04A

s0

242

270

990

661

033

382

270

600

282

761

280

800

003

380

831

180

000

100

020

020

000

230

040

05

Tot

al97

78

100

0999

32

063

985

110

067

996

20

5693

94

100

5299

33

110

989

610

063

997

30

3796

52

102

4099

03

153

982

010

248

999

70

80

At

Au

000

003

001

001

000

001

001

000

000

003

000

00

000

001

000

000

000

001

000

000

000

002

000

000

Ag

000

002

001

001

000

001

001

000

000

004

001

00

000

002

001

000

000

056

007

013

000

006

001

001

S65

44

665

065

93

029

646

966

26

654

50

4164

91

667

765

87

04

649

266

88

662

40

5866

32

668

366

58

016

658

367

36

667

00

32Sb

000

001

000

000

000

004

001

001

000

006

001

00

000

001

000

000

000

001

000

000

000

002

000

000

Fe33

07

338

533

45

020

322

133

94

330

20

4332

92

342

733

43

03

321

433

48

329

40

3132

54

335

133

15

021

323

834

08

331

90

32C

o0

000

060

020

010

010

350

110

110

000

040

010

00

000

460

170

130

010

020

010

000

000

080

010

01N

i0

000

020

000

010

000

620

120

180

000

040

000

00

000

700

150

180

000

010

000

000

000

050

010

01C

u0

000

130

010

030

000

110

010

020

000

090

010

00

000

050

010

010

010

400

130

100

000

440

020

07Z

n0

000

180

020

040

000

010

010

010

000

020

010

00

000

020

010

010

000

020

010

010

000

240

010

03A

s0

131

230

530

350

561

841

230

330

151

510

630

430

001

840

450

640

000

050

010

010

000

120

020

03

A

type

I(c

ores

)B

ty

peI

(pol

ygon

alba

nds)

C

ty

peI

(irr

egul

arba

nds)

D

ty

peII

E

ty

peII

IF

type

IV

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion

TA

BL

E3

Che

mis

try

of

ne-g

rain

edpy

rite

(lt20

m m)

A(n

=17

)B

(n=

9)C

(n=

18)

D(n

=33

)E

(n=

11)

F(n

=13

)W

tM

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)

Au

000

006

003

001

000

005

002

002

000

004

002

001

000

005

002

001

000

004

002

001

000

005

002

001

Ag

000

006

003

002

000

006

002

002

000

016

007

005

000

020

004

004

000

005

002

001

000

008

003

003

S52

46

537

953

23

036

486

053

09

518

61

4550

25

530

851

85

068

496

253

79

514

51

2151

75

534

652

68

057

517

553

66

530

60

53Sb

001

003

002

001

000

002

001

001

007

046

018

008

000

141

030

042

000

003

001

001

000

008

002

002

Fe44

53

465

245

91

043

411

145

43

441

91

4441

93

461

644

50

119

416

146

29

437

31

4245

68

466

246

27

024

452

746

33

457

30

37C

o0

010

050

020

010

040

100

070

020

010

040

020

010

000

040

020

010

010

050

030

010

010

030

020

01N

i0

000

020

000

010

010

110

040

030

000

140

050

050

000

010

000

000

000

040

010

010

000

080

020

03C

u0

000

050

020

010

000

020

000

010

000

940

250

270

001

260

190

270

010

390

130

110

001

320

570

39Z

n0

000

030

010

010

000

020

010

010

000

180

060

060

000

100

010

020

000

070

020

020

000

190

040

05A

s0

110

660

210

130

000

290

110

080

534

492

361

100

086

113

761

840

000

080

020

030

000

120

020

03

Tot

al97

44

100

6499

50

073

899

698

76

963

32

9198

20

100

4499

37

058

980

610

056

995

30

7197

95

999

299

22

058

980

610

092

995

30

93

At

Au

000

001

001

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

Ag

000

002

001

001

000

002

001

001

000

006

003

002

000

008

002

002

000

002

001

000

000

003

001

001

S66

45

672

066

75

019

667

367

28

670

20

1865

27

666

565

88

030

647

566

93

656

20

6466

03

667

766

35

026

660

566

97

665

80

29Sb

000

001

001

000

000

001

000

000

003

015

006

003

000

049

010

014

000

001

000

000

000

003

001

001

Fe32

64

332

833

05

017

325

233

03

327

90

1831

27

332

032

46

060

311

833

08

320

10

6133

09

337

933

47

025

326

133

89

329

50

35C

o0

000

030

010

010

020

070

050

020

010

030

010

010

000

020

010

010

000

030

020

010

000

020

010

01N

i0

000

010

000

000

010

080

030

020

000

100

030

040

000

010

000

000

000

030

010

010

000

050

010

02C

u0

000

030

010

010

000

010

000

000

000

610

160

170

000

830

130

180

010

250

080

070

000

830

360

25Z

n0

000

020

010

010

000

020

010

010

000

110

040

030

000

060

010

010

000

040

010

010

000

120

020

03A

s0

060

350

120

070

000

160

060

050

292

501

290

610

043

362

061

020

000

050

010

010

000

070

010

02

A

type

V(f

ram

boid

sse

nsu

stri

cto)

B

ty

peV

(pse

udof

ram

boid

s)

C

type

VI

(col

lom

orph

icpo

rous

pyri

te)

Dt

ype

VI

(bro

wn

collo

mor

phic

pyri

te)

E

type

VII

(mic

ro-g

eode

s)

Fty

peV

II(p

yrit

ein

terg

row

ths

inch

alco

pyri

te)

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion





marked area

1068








1069








00

05

10

15

20

25

30

6 4 5 65 0 6 55 6 6 0 6 6 5 6 7 0 S (at)

Type I

Type VI

00

05

10

15

20

25

30

31 0 31 5 32 0 32 5 33 0 33 5 Fe (at)

0

2

4

6

8

10

12

14

0 02 04 06 08 1 12 14 As (at)

Type I (ii)

(iii)

(i)

As

(at

)Fr

eque

ncy

As

(at

)

Type I

Type VI

a

b

c



1070







000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)






1071







1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080



Geological context






Ore mineralization



1061











1062















Total 9737 9884 9829 046 9774 10067 9929 071 987 992 989 018




1063



1064









000

004

008

012

016

000 020 040 060 080

As (at)

000

010

020

030

040

050

060

070

6600 6650 6700

S (at)

Sb

(at

)

As

(at

)

a b




1065

TA

BL

E2

Che

mis

try

ofm

ediu

m-

toco

arse

-gra

ined

pyri

te(gt

20m m

)

A(n

=19

)B

(n=

21)

C(n

=39

)D

(n=

37)

E(n

=18

)F

(n=

107)

Wt

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Au

000

016

003

004

000

006

003

002

000

016

003

003

000

005

002

001

000

005

002

001

000

010

002

002

Ag

000

006

001

001

000

003

001

001

000

009

002

002

000

005

001

001

000

147

018

035

000

017

002

002

S51

31

530

352

16

043

505

052

62

515

90

6449

39

536

152

10

078

508

753

83

527

20

7952

07

535

352

79

044

515

554

85

533

00

54Sb

000

003

001

001

000

011

002

002

000

019

003

004

000

004

001

001

000

004

001

001

000

006

001

001

Fe45

38

465

646

10

032

443

946

06

453

30

5344

51

467

546

05

049

443

946

41

456

60

6044

42

465

245

78

052

446

846

98

461

90

43C

o0

000

090

030

020

020

510

170

160

000

070

020

010

010

690

250

190

010

030

020

010

000

120

030

02N

i0

000

030

000

010

000

900

170

270

000

050

010

010

001

010

210

260

000

010

000

000

000

080

010

01C

u0

000

190

020

040

000

160

020

030

000

140

020

030

000

080

010

020

010

620

200

160

000

700

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300

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020

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000

040

010

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000

040

010

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000

040

010

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000

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020

04A

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270

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600

282

761

280

800

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102

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153

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80

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Au

000

003

001

001

000

001

001

000

000

003

000

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000

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000

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000

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000

000

000

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000

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001

001

000

001

001

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87

04

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266

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40

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32

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016

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367

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000

001

000

000

000

004

001

001

000

006

001

00

000

001

000

000

000

001

000

000

000

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07

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45

020

322

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94

330

20

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110

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120

180

000

040

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700

150

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450

640

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A

type

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ores

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ty

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(pol

ygon

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C

ty

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(irr

egul

arba

nds)

D

ty

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E

ty

peII

IF

type

IV

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion

TA

BL

E3

Che

mis

try

of

ne-g

rain

edpy

rite

(lt20

m m)

A(n

=17

)B

(n=

9)C

(n=

18)

D(n

=33

)E

(n=

11)

F(n

=13

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tM

in

Max

A

ves

d

(1s

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in

Max

A

ves

d

(1s

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in

Max

A

ves

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(1s

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in

Max

A

ves

d

(1s

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in

Max

A

ves

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(1s

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in

Max

A

ves

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(1s

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Au

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006

003

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000

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002

002

000

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000

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000

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000

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000

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530

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514

51

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68

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517

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66

530

60

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003

002

001

000

002

001

001

007

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000

141

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042

000

003

001

001

000

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002

002

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245

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411

145

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119

416

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29

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250

270

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260

190

270

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390

130

110

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320

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010

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000

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010

000

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060

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000

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000

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020

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Tot

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100

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980

610

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93

At

Au

000

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000

000

001

000

000

000

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000

000

000

001

000

000

000

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000

000

000

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000

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000

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000

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45

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367

28

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20

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88

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647

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93

656

20

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667

766

35

026

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97

665

80

29Sb

000

001

001

000

000

001

000

000

003

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006

003

000

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010

014

000

001

000

000

000

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001

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64

332

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05

017

325

233

03

327

90

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27

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311

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08

320

10

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133

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50

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000

020

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000

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020

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000

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100

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000

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160

170

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130

180

010

250

080

070

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360

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010

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000

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010

000

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s0

060

350

120

070

000

160

060

050

292

501

290

610

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362

061

020

000

050

010

010

000

070

010

02

A

type

V(f

ram

boid

sse

nsu

stri

cto)

B

ty

peV

(pse

udof

ram

boid

s)

C

type

VI

(col

lom

orph

icpo

rous

pyri

te)

Dt

ype

VI

(bro

wn

collo

mor

phic

pyri

te)

E

type

VII

(mic

ro-g

eode

s)

Fty

peV

II(p

yrit

ein

terg

row

ths

inch

alco

pyri

te)

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion





marked area

1068








1069








00

05

10

15

20

25

30

6 4 5 65 0 6 55 6 6 0 6 6 5 6 7 0 S (at)

Type I

Type VI

00

05

10

15

20

25

30

31 0 31 5 32 0 32 5 33 0 33 5 Fe (at)

0

2

4

6

8

10

12

14

0 02 04 06 08 1 12 14 As (at)

Type I (ii)

(iii)

(i)

As

(at

)Fr

eque

ncy

As

(at

)

Type I

Type VI

a

b

c



1070







000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)






1071







1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080












1062















Total 9737 9884 9829 046 9774 10067 9929 071 987 992 989 018




1063



1064









000

004

008

012

016

000 020 040 060 080

As (at)

000

010

020

030

040

050

060

070

6600 6650 6700

S (at)

Sb

(at

)

As

(at

)

a b




1065

TA

BL

E2

Che

mis

try

ofm

ediu

m-

toco

arse

-gra

ined

pyri

te(gt

20m m

)

A(n

=19

)B

(n=

21)

C(n

=39

)D

(n=

37)

E(n

=18

)F

(n=

107)

Wt

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Au

000

016

003

004

000

006

003

002

000

016

003

003

000

005

002

001

000

005

002

001

000

010

002

002

Ag

000

006

001

001

000

003

001

001

000

009

002

002

000

005

001

001

000

147

018

035

000

017

002

002

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31

530

352

16

043

505

052

62

515

90

6449

39

536

152

10

078

508

753

83

527

20

7952

07

535

352

79

044

515

554

85

533

00

54Sb

000

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001

001

000

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002

002

000

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003

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000

004

001

001

000

004

001

001

000

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001

001

Fe45

38

465

646

10

032

443

946

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453

30

5344

51

467

546

05

049

443

946

41

456

60

6044

42

465

245

78

052

446

846

98

461

90

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020

020

510

170

160

000

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020

010

010

690

250

190

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020

010

000

120

030

02N

i0

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000

010

000

900

170

270

000

050

010

010

001

010

210

260

000

010

000

000

000

080

010

01C

u0

000

190

020

040

000

160

020

030

000

140

020

030

000

080

010

020

010

620

200

160

000

700

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11Z

n0

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000

040

010

010

000

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000

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010

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000

390

020

04A

s0

242

270

990

661

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382

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600

282

761

280

800

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380

831

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000

100

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020

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230

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05

Tot

al97

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100

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20

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94

100

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110

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30

3796

52

102

4099

03

153

982

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248

999

70

80

At

Au

000

003

001

001

000

001

001

000

000

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000

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000

001

000

000

000

001

000

000

000

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Ag

000

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001

001

000

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001

000

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000

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000

000

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007

013

000

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001

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S65

44

665

065

93

029

646

966

26

654

50

4164

91

667

765

87

04

649

266

88

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40

5866

32

668

366

58

016

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667

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000

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000

000

000

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001

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000

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001

00

000

001

000

000

000

001

000

000

000

002

000

000

Fe33

07

338

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45

020

322

133

94

330

20

4332

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342

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03

321

433

48

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335

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15

021

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350

110

110

000

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020

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000

000

080

010

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i0

000

020

000

010

000

620

120

180

000

040

000

00

000

700

150

180

000

010

000

000

000

050

010

01C

u0

000

130

010

030

000

110

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000

090

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00

000

050

010

010

010

400

130

100

000

440

020

07Z

n0

000

180

020

040

000

010

010

010

000

020

010

00

000

020

010

010

000

020

010

010

000

240

010

03A

s0

131

230

530

350

561

841

230

330

151

510

630

430

001

840

450

640

000

050

010

010

000

120

020

03

A

type

I(c

ores

)B

ty

peI

(pol

ygon

alba

nds)

C

ty

peI

(irr

egul

arba

nds)

D

ty

peII

E

ty

peII

IF

type

IV

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion

TA

BL

E3

Che

mis

try

of

ne-g

rain

edpy

rite

(lt20

m m)

A(n

=17

)B

(n=

9)C

(n=

18)

D(n

=33

)E

(n=

11)

F(n

=13

)W

tM

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)

Au

000

006

003

001

000

005

002

002

000

004

002

001

000

005

002

001

000

004

002

001

000

005

002

001

Ag

000

006

003

002

000

006

002

002

000

016

007

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000

020

004

004

000

005

002

001

000

008

003

003

S52

46

537

953

23

036

486

053

09

518

61

4550

25

530

851

85

068

496

253

79

514

51

2151

75

534

652

68

057

517

553

66

530

60

53Sb

001

003

002

001

000

002

001

001

007

046

018

008

000

141

030

042

000

003

001

001

000

008

002

002

Fe44

53

465

245

91

043

411

145

43

441

91

4441

93

461

644

50

119

416

146

29

437

31

4245

68

466

246

27

024

452

746

33

457

30

37C

o0

010

050

020

010

040

100

070

020

010

040

020

010

000

040

020

010

010

050

030

010

010

030

020

01N

i0

000

020

000

010

010

110

040

030

000

140

050

050

000

010

000

000

000

040

010

010

000

080

020

03C

u0

000

050

020

010

000

020

000

010

000

940

250

270

001

260

190

270

010

390

130

110

001

320

570

39Z

n0

000

030

010

010

000

020

010

010

000

180

060

060

000

100

010

020

000

070

020

020

000

190

040

05A

s0

110

660

210

130

000

290

110

080

534

492

361

100

086

113

761

840

000

080

020

030

000

120

020

03

Tot

al97

44

100

6499

50

073

899

698

76

963

32

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20

100

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37

058

980

610

056

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30

7197

95

999

299

22

058

980

610

092

995

30

93

At

Au

000

001

001

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

Ag

000

002

001

001

000

002

001

001

000

006

003

002

000

008

002

002

000

002

001

000

000

003

001

001

S66

45

672

066

75

019

667

367

28

670

20

1865

27

666

565

88

030

647

566

93

656

20

6466

03

667

766

35

026

660

566

97

665

80

29Sb

000

001

001

000

000

001

000

000

003

015

006

003

000

049

010

014

000

001

000

000

000

003

001

001

Fe32

64

332

833

05

017

325

233

03

327

90

1831

27

332

032

46

060

311

833

08

320

10

6133

09

337

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47

025

326

133

89

329

50

35C

o0

000

030

010

010

020

070

050

020

010

030

010

010

000

020

010

010

000

030

020

010

000

020

010

01N

i0

000

010

000

000

010

080

030

020

000

100

030

040

000

010

000

000

000

030

010

010

000

050

010

02C

u0

000

030

010

010

000

010

000

000

000

610

160

170

000

830

130

180

010

250

080

070

000

830

360

25Z

n0

000

020

010

010

000

020

010

010

000

110

040

030

000

060

010

010

000

040

010

010

000

120

020

03A

s0

060

350

120

070

000

160

060

050

292

501

290

610

043

362

061

020

000

050

010

010

000

070

010

02

A

type

V(f

ram

boid

sse

nsu

stri

cto)

B

ty

peV

(pse

udof

ram

boid

s)

C

type

VI

(col

lom

orph

icpo

rous

pyri

te)

Dt

ype

VI

(bro

wn

collo

mor

phic

pyri

te)

E

type

VII

(mic

ro-g

eode

s)

Fty

peV

II(p

yrit

ein

terg

row

ths

inch

alco

pyri

te)

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion





marked area

1068








1069








00

05

10

15

20

25

30

6 4 5 65 0 6 55 6 6 0 6 6 5 6 7 0 S (at)

Type I

Type VI

00

05

10

15

20

25

30

31 0 31 5 32 0 32 5 33 0 33 5 Fe (at)

0

2

4

6

8

10

12

14

0 02 04 06 08 1 12 14 As (at)

Type I (ii)

(iii)

(i)

As

(at

)Fr

eque

ncy

As

(at

)

Type I

Type VI

a

b

c



1070







000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)






1071







1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080















Total 9737 9884 9829 046 9774 10067 9929 071 987 992 989 018




1063



1064









000

004

008

012

016

000 020 040 060 080

As (at)

000

010

020

030

040

050

060

070

6600 6650 6700

S (at)

Sb

(at

)

As

(at

)

a b




1065

TA

BL

E2

Che

mis

try

ofm

ediu

m-

toco

arse

-gra

ined

pyri

te(gt

20m m

)

A(n

=19

)B

(n=

21)

C(n

=39

)D

(n=

37)

E(n

=18

)F

(n=

107)

Wt

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Au

000

016

003

004

000

006

003

002

000

016

003

003

000

005

002

001

000

005

002

001

000

010

002

002

Ag

000

006

001

001

000

003

001

001

000

009

002

002

000

005

001

001

000

147

018

035

000

017

002

002

S51

31

530

352

16

043

505

052

62

515

90

6449

39

536

152

10

078

508

753

83

527

20

7952

07

535

352

79

044

515

554

85

533

00

54Sb

000

003

001

001

000

011

002

002

000

019

003

004

000

004

001

001

000

004

001

001

000

006

001

001

Fe45

38

465

646

10

032

443

946

06

453

30

5344

51

467

546

05

049

443

946

41

456

60

6044

42

465

245

78

052

446

846

98

461

90

43C

o0

000

090

030

020

020

510

170

160

000

070

020

010

010

690

250

190

010

030

020

010

000

120

030

02N

i0

000

030

000

010

000

900

170

270

000

050

010

010

001

010

210

260

000

010

000

000

000

080

010

01C

u0

000

190

020

040

000

160

020

030

000

140

020

030

000

080

010

020

010

620

200

160

000

700

040

11Z

n0

000

300

030

070

000

020

010

010

000

040

010

010

000

040

010

010

000

040

010

010

000

390

020

04A

s0

242

270

990

661

033

382

270

600

282

761

280

800

003

380

831

180

000

100

020

020

000

230

040

05

Tot

al97

78

100

0999

32

063

985

110

067

996

20

5693

94

100

5299

33

110

989

610

063

997

30

3796

52

102

4099

03

153

982

010

248

999

70

80

At

Au

000

003

001

001

000

001

001

000

000

003

000

00

000

001

000

000

000

001

000

000

000

002

000

000

Ag

000

002

001

001

000

001

001

000

000

004

001

00

000

002

001

000

000

056

007

013

000

006

001

001

S65

44

665

065

93

029

646

966

26

654

50

4164

91

667

765

87

04

649

266

88

662

40

5866

32

668

366

58

016

658

367

36

667

00

32Sb

000

001

000

000

000

004

001

001

000

006

001

00

000

001

000

000

000

001

000

000

000

002

000

000

Fe33

07

338

533

45

020

322

133

94

330

20

4332

92

342

733

43

03

321

433

48

329

40

3132

54

335

133

15

021

323

834

08

331

90

32C

o0

000

060

020

010

010

350

110

110

000

040

010

00

000

460

170

130

010

020

010

000

000

080

010

01N

i0

000

020

000

010

000

620

120

180

000

040

000

00

000

700

150

180

000

010

000

000

000

050

010

01C

u0

000

130

010

030

000

110

010

020

000

090

010

00

000

050

010

010

010

400

130

100

000

440

020

07Z

n0

000

180

020

040

000

010

010

010

000

020

010

00

000

020

010

010

000

020

010

010

000

240

010

03A

s0

131

230

530

350

561

841

230

330

151

510

630

430

001

840

450

640

000

050

010

010

000

120

020

03

A

type

I(c

ores

)B

ty

peI

(pol

ygon

alba

nds)

C

ty

peI

(irr

egul

arba

nds)

D

ty

peII

E

ty

peII

IF

type

IV

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion

TA

BL

E3

Che

mis

try

of

ne-g

rain

edpy

rite

(lt20

m m)

A(n

=17

)B

(n=

9)C

(n=

18)

D(n

=33

)E

(n=

11)

F(n

=13

)W

tM

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)

Au

000

006

003

001

000

005

002

002

000

004

002

001

000

005

002

001

000

004

002

001

000

005

002

001

Ag

000

006

003

002

000

006

002

002

000

016

007

005

000

020

004

004

000

005

002

001

000

008

003

003

S52

46

537

953

23

036

486

053

09

518

61

4550

25

530

851

85

068

496

253

79

514

51

2151

75

534

652

68

057

517

553

66

530

60

53Sb

001

003

002

001

000

002

001

001

007

046

018

008

000

141

030

042

000

003

001

001

000

008

002

002

Fe44

53

465

245

91

043

411

145

43

441

91

4441

93

461

644

50

119

416

146

29

437

31

4245

68

466

246

27

024

452

746

33

457

30

37C

o0

010

050

020

010

040

100

070

020

010

040

020

010

000

040

020

010

010

050

030

010

010

030

020

01N

i0

000

020

000

010

010

110

040

030

000

140

050

050

000

010

000

000

000

040

010

010

000

080

020

03C

u0

000

050

020

010

000

020

000

010

000

940

250

270

001

260

190

270

010

390

130

110

001

320

570

39Z

n0

000

030

010

010

000

020

010

010

000

180

060

060

000

100

010

020

000

070

020

020

000

190

040

05A

s0

110

660

210

130

000

290

110

080

534

492

361

100

086

113

761

840

000

080

020

030

000

120

020

03

Tot

al97

44

100

6499

50

073

899

698

76

963

32

9198

20

100

4499

37

058

980

610

056

995

30

7197

95

999

299

22

058

980

610

092

995

30

93

At

Au

000

001

001

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

Ag

000

002

001

001

000

002

001

001

000

006

003

002

000

008

002

002

000

002

001

000

000

003

001

001

S66

45

672

066

75

019

667

367

28

670

20

1865

27

666

565

88

030

647

566

93

656

20

6466

03

667

766

35

026

660

566

97

665

80

29Sb

000

001

001

000

000

001

000

000

003

015

006

003

000

049

010

014

000

001

000

000

000

003

001

001

Fe32

64

332

833

05

017

325

233

03

327

90

1831

27

332

032

46

060

311

833

08

320

10

6133

09

337

933

47

025

326

133

89

329

50

35C

o0

000

030

010

010

020

070

050

020

010

030

010

010

000

020

010

010

000

030

020

010

000

020

010

01N

i0

000

010

000

000

010

080

030

020

000

100

030

040

000

010

000

000

000

030

010

010

000

050

010

02C

u0

000

030

010

010

000

010

000

000

000

610

160

170

000

830

130

180

010

250

080

070

000

830

360

25Z

n0

000

020

010

010

000

020

010

010

000

110

040

030

000

060

010

010

000

040

010

010

000

120

020

03A

s0

060

350

120

070

000

160

060

050

292

501

290

610

043

362

061

020

000

050

010

010

000

070

010

02

A

type

V(f

ram

boid

sse

nsu

stri

cto)

B

ty

peV

(pse

udof

ram

boid

s)

C

type

VI

(col

lom

orph

icpo

rous

pyri

te)

Dt

ype

VI

(bro

wn

collo

mor

phic

pyri

te)

E

type

VII

(mic

ro-g

eode

s)

Fty

peV

II(p

yrit

ein

terg

row

ths

inch

alco

pyri

te)

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion





marked area

1068








1069








00

05

10

15

20

25

30

6 4 5 65 0 6 55 6 6 0 6 6 5 6 7 0 S (at)

Type I

Type VI

00

05

10

15

20

25

30

31 0 31 5 32 0 32 5 33 0 33 5 Fe (at)

0

2

4

6

8

10

12

14

0 02 04 06 08 1 12 14 As (at)

Type I (ii)

(iii)

(i)

As

(at

)Fr

eque

ncy

As

(at

)

Type I

Type VI

a

b

c



1070







000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)






1071







1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080




1064









000

004

008

012

016

000 020 040 060 080

As (at)

000

010

020

030

040

050

060

070

6600 6650 6700

S (at)

Sb

(at

)

As

(at

)

a b




1065

TA

BL

E2

Che

mis

try

ofm

ediu

m-

toco

arse

-gra

ined

pyri

te(gt

20m m

)

A(n

=19

)B

(n=

21)

C(n

=39

)D

(n=

37)

E(n

=18

)F

(n=

107)

Wt

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Au

000

016

003

004

000

006

003

002

000

016

003

003

000

005

002

001

000

005

002

001

000

010

002

002

Ag

000

006

001

001

000

003

001

001

000

009

002

002

000

005

001

001

000

147

018

035

000

017

002

002

S51

31

530

352

16

043

505

052

62

515

90

6449

39

536

152

10

078

508

753

83

527

20

7952

07

535

352

79

044

515

554

85

533

00

54Sb

000

003

001

001

000

011

002

002

000

019

003

004

000

004

001

001

000

004

001

001

000

006

001

001

Fe45

38

465

646

10

032

443

946

06

453

30

5344

51

467

546

05

049

443

946

41

456

60

6044

42

465

245

78

052

446

846

98

461

90

43C

o0

000

090

030

020

020

510

170

160

000

070

020

010

010

690

250

190

010

030

020

010

000

120

030

02N

i0

000

030

000

010

000

900

170

270

000

050

010

010

001

010

210

260

000

010

000

000

000

080

010

01C

u0

000

190

020

040

000

160

020

030

000

140

020

030

000

080

010

020

010

620

200

160

000

700

040

11Z

n0

000

300

030

070

000

020

010

010

000

040

010

010

000

040

010

010

000

040

010

010

000

390

020

04A

s0

242

270

990

661

033

382

270

600

282

761

280

800

003

380

831

180

000

100

020

020

000

230

040

05

Tot

al97

78

100

0999

32

063

985

110

067

996

20

5693

94

100

5299

33

110

989

610

063

997

30

3796

52

102

4099

03

153

982

010

248

999

70

80

At

Au

000

003

001

001

000

001

001

000

000

003

000

00

000

001

000

000

000

001

000

000

000

002

000

000

Ag

000

002

001

001

000

001

001

000

000

004

001

00

000

002

001

000

000

056

007

013

000

006

001

001

S65

44

665

065

93

029

646

966

26

654

50

4164

91

667

765

87

04

649

266

88

662

40

5866

32

668

366

58

016

658

367

36

667

00

32Sb

000

001

000

000

000

004

001

001

000

006

001

00

000

001

000

000

000

001

000

000

000

002

000

000

Fe33

07

338

533

45

020

322

133

94

330

20

4332

92

342

733

43

03

321

433

48

329

40

3132

54

335

133

15

021

323

834

08

331

90

32C

o0

000

060

020

010

010

350

110

110

000

040

010

00

000

460

170

130

010

020

010

000

000

080

010

01N

i0

000

020

000

010

000

620

120

180

000

040

000

00

000

700

150

180

000

010

000

000

000

050

010

01C

u0

000

130

010

030

000

110

010

020

000

090

010

00

000

050

010

010

010

400

130

100

000

440

020

07Z

n0

000

180

020

040

000

010

010

010

000

020

010

00

000

020

010

010

000

020

010

010

000

240

010

03A

s0

131

230

530

350

561

841

230

330

151

510

630

430

001

840

450

640

000

050

010

010

000

120

020

03

A

type

I(c

ores

)B

ty

peI

(pol

ygon

alba

nds)

C

ty

peI

(irr

egul

arba

nds)

D

ty

peII

E

ty

peII

IF

type

IV

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion

TA

BL

E3

Che

mis

try

of

ne-g

rain

edpy

rite

(lt20

m m)

A(n

=17

)B

(n=

9)C

(n=

18)

D(n

=33

)E

(n=

11)

F(n

=13

)W

tM

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)

Au

000

006

003

001

000

005

002

002

000

004

002

001

000

005

002

001

000

004

002

001

000

005

002

001

Ag

000

006

003

002

000

006

002

002

000

016

007

005

000

020

004

004

000

005

002

001

000

008

003

003

S52

46

537

953

23

036

486

053

09

518

61

4550

25

530

851

85

068

496

253

79

514

51

2151

75

534

652

68

057

517

553

66

530

60

53Sb

001

003

002

001

000

002

001

001

007

046

018

008

000

141

030

042

000

003

001

001

000

008

002

002

Fe44

53

465

245

91

043

411

145

43

441

91

4441

93

461

644

50

119

416

146

29

437

31

4245

68

466

246

27

024

452

746

33

457

30

37C

o0

010

050

020

010

040

100

070

020

010

040

020

010

000

040

020

010

010

050

030

010

010

030

020

01N

i0

000

020

000

010

010

110

040

030

000

140

050

050

000

010

000

000

000

040

010

010

000

080

020

03C

u0

000

050

020

010

000

020

000

010

000

940

250

270

001

260

190

270

010

390

130

110

001

320

570

39Z

n0

000

030

010

010

000

020

010

010

000

180

060

060

000

100

010

020

000

070

020

020

000

190

040

05A

s0

110

660

210

130

000

290

110

080

534

492

361

100

086

113

761

840

000

080

020

030

000

120

020

03

Tot

al97

44

100

6499

50

073

899

698

76

963

32

9198

20

100

4499

37

058

980

610

056

995

30

7197

95

999

299

22

058

980

610

092

995

30

93

At

Au

000

001

001

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

Ag

000

002

001

001

000

002

001

001

000

006

003

002

000

008

002

002

000

002

001

000

000

003

001

001

S66

45

672

066

75

019

667

367

28

670

20

1865

27

666

565

88

030

647

566

93

656

20

6466

03

667

766

35

026

660

566

97

665

80

29Sb

000

001

001

000

000

001

000

000

003

015

006

003

000

049

010

014

000

001

000

000

000

003

001

001

Fe32

64

332

833

05

017

325

233

03

327

90

1831

27

332

032

46

060

311

833

08

320

10

6133

09

337

933

47

025

326

133

89

329

50

35C

o0

000

030

010

010

020

070

050

020

010

030

010

010

000

020

010

010

000

030

020

010

000

020

010

01N

i0

000

010

000

000

010

080

030

020

000

100

030

040

000

010

000

000

000

030

010

010

000

050

010

02C

u0

000

030

010

010

000

010

000

000

000

610

160

170

000

830

130

180

010

250

080

070

000

830

360

25Z

n0

000

020

010

010

000

020

010

010

000

110

040

030

000

060

010

010

000

040

010

010

000

120

020

03A

s0

060

350

120

070

000

160

060

050

292

501

290

610

043

362

061

020

000

050

010

010

000

070

010

02

A

type

V(f

ram

boid

sse

nsu

stri

cto)

B

ty

peV

(pse

udof

ram

boid

s)

C

type

VI

(col

lom

orph

icpo

rous

pyri

te)

Dt

ype

VI

(bro

wn

collo

mor

phic

pyri

te)

E

type

VII

(mic

ro-g

eode

s)

Fty

peV

II(p

yrit

ein

terg

row

ths

inch

alco

pyri

te)

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion





marked area

1068








1069








00

05

10

15

20

25

30

6 4 5 65 0 6 55 6 6 0 6 6 5 6 7 0 S (at)

Type I

Type VI

00

05

10

15

20

25

30

31 0 31 5 32 0 32 5 33 0 33 5 Fe (at)

0

2

4

6

8

10

12

14

0 02 04 06 08 1 12 14 As (at)

Type I (ii)

(iii)

(i)

As

(at

)Fr

eque

ncy

As

(at

)

Type I

Type VI

a

b

c



1070







000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)






1071







1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080









000

004

008

012

016

000 020 040 060 080

As (at)

000

010

020

030

040

050

060

070

6600 6650 6700

S (at)

Sb

(at

)

As

(at

)

a b




1065

TA

BL

E2

Che

mis

try

ofm

ediu

m-

toco

arse

-gra

ined

pyri

te(gt

20m m

)

A(n

=19

)B

(n=

21)

C(n

=39

)D

(n=

37)

E(n

=18

)F

(n=

107)

Wt

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Au

000

016

003

004

000

006

003

002

000

016

003

003

000

005

002

001

000

005

002

001

000

010

002

002

Ag

000

006

001

001

000

003

001

001

000

009

002

002

000

005

001

001

000

147

018

035

000

017

002

002

S51

31

530

352

16

043

505

052

62

515

90

6449

39

536

152

10

078

508

753

83

527

20

7952

07

535

352

79

044

515

554

85

533

00

54Sb

000

003

001

001

000

011

002

002

000

019

003

004

000

004

001

001

000

004

001

001

000

006

001

001

Fe45

38

465

646

10

032

443

946

06

453

30

5344

51

467

546

05

049

443

946

41

456

60

6044

42

465

245

78

052

446

846

98

461

90

43C

o0

000

090

030

020

020

510

170

160

000

070

020

010

010

690

250

190

010

030

020

010

000

120

030

02N

i0

000

030

000

010

000

900

170

270

000

050

010

010

001

010

210

260

000

010

000

000

000

080

010

01C

u0

000

190

020

040

000

160

020

030

000

140

020

030

000

080

010

020

010

620

200

160

000

700

040

11Z

n0

000

300

030

070

000

020

010

010

000

040

010

010

000

040

010

010

000

040

010

010

000

390

020

04A

s0

242

270

990

661

033

382

270

600

282

761

280

800

003

380

831

180

000

100

020

020

000

230

040

05

Tot

al97

78

100

0999

32

063

985

110

067

996

20

5693

94

100

5299

33

110

989

610

063

997

30

3796

52

102

4099

03

153

982

010

248

999

70

80

At

Au

000

003

001

001

000

001

001

000

000

003

000

00

000

001

000

000

000

001

000

000

000

002

000

000

Ag

000

002

001

001

000

001

001

000

000

004

001

00

000

002

001

000

000

056

007

013

000

006

001

001

S65

44

665

065

93

029

646

966

26

654

50

4164

91

667

765

87

04

649

266

88

662

40

5866

32

668

366

58

016

658

367

36

667

00

32Sb

000

001

000

000

000

004

001

001

000

006

001

00

000

001

000

000

000

001

000

000

000

002

000

000

Fe33

07

338

533

45

020

322

133

94

330

20

4332

92

342

733

43

03

321

433

48

329

40

3132

54

335

133

15

021

323

834

08

331

90

32C

o0

000

060

020

010

010

350

110

110

000

040

010

00

000

460

170

130

010

020

010

000

000

080

010

01N

i0

000

020

000

010

000

620

120

180

000

040

000

00

000

700

150

180

000

010

000

000

000

050

010

01C

u0

000

130

010

030

000

110

010

020

000

090

010

00

000

050

010

010

010

400

130

100

000

440

020

07Z

n0

000

180

020

040

000

010

010

010

000

020

010

00

000

020

010

010

000

020

010

010

000

240

010

03A

s0

131

230

530

350

561

841

230

330

151

510

630

430

001

840

450

640

000

050

010

010

000

120

020

03

A

type

I(c

ores

)B

ty

peI

(pol

ygon

alba

nds)

C

ty

peI

(irr

egul

arba

nds)

D

ty

peII

E

ty

peII

IF

type

IV

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion

TA

BL

E3

Che

mis

try

of

ne-g

rain

edpy

rite

(lt20

m m)

A(n

=17

)B

(n=

9)C

(n=

18)

D(n

=33

)E

(n=

11)

F(n

=13

)W

tM

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)

Au

000

006

003

001

000

005

002

002

000

004

002

001

000

005

002

001

000

004

002

001

000

005

002

001

Ag

000

006

003

002

000

006

002

002

000

016

007

005

000

020

004

004

000

005

002

001

000

008

003

003

S52

46

537

953

23

036

486

053

09

518

61

4550

25

530

851

85

068

496

253

79

514

51

2151

75

534

652

68

057

517

553

66

530

60

53Sb

001

003

002

001

000

002

001

001

007

046

018

008

000

141

030

042

000

003

001

001

000

008

002

002

Fe44

53

465

245

91

043

411

145

43

441

91

4441

93

461

644

50

119

416

146

29

437

31

4245

68

466

246

27

024

452

746

33

457

30

37C

o0

010

050

020

010

040

100

070

020

010

040

020

010

000

040

020

010

010

050

030

010

010

030

020

01N

i0

000

020

000

010

010

110

040

030

000

140

050

050

000

010

000

000

000

040

010

010

000

080

020

03C

u0

000

050

020

010

000

020

000

010

000

940

250

270

001

260

190

270

010

390

130

110

001

320

570

39Z

n0

000

030

010

010

000

020

010

010

000

180

060

060

000

100

010

020

000

070

020

020

000

190

040

05A

s0

110

660

210

130

000

290

110

080

534

492

361

100

086

113

761

840

000

080

020

030

000

120

020

03

Tot

al97

44

100

6499

50

073

899

698

76

963

32

9198

20

100

4499

37

058

980

610

056

995

30

7197

95

999

299

22

058

980

610

092

995

30

93

At

Au

000

001

001

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

Ag

000

002

001

001

000

002

001

001

000

006

003

002

000

008

002

002

000

002

001

000

000

003

001

001

S66

45

672

066

75

019

667

367

28

670

20

1865

27

666

565

88

030

647

566

93

656

20

6466

03

667

766

35

026

660

566

97

665

80

29Sb

000

001

001

000

000

001

000

000

003

015

006

003

000

049

010

014

000

001

000

000

000

003

001

001

Fe32

64

332

833

05

017

325

233

03

327

90

1831

27

332

032

46

060

311

833

08

320

10

6133

09

337

933

47

025

326

133

89

329

50

35C

o0

000

030

010

010

020

070

050

020

010

030

010

010

000

020

010

010

000

030

020

010

000

020

010

01N

i0

000

010

000

000

010

080

030

020

000

100

030

040

000

010

000

000

000

030

010

010

000

050

010

02C

u0

000

030

010

010

000

010

000

000

000

610

160

170

000

830

130

180

010

250

080

070

000

830

360

25Z

n0

000

020

010

010

000

020

010

010

000

110

040

030

000

060

010

010

000

040

010

010

000

120

020

03A

s0

060

350

120

070

000

160

060

050

292

501

290

610

043

362

061

020

000

050

010

010

000

070

010

02

A

type

V(f

ram

boid

sse

nsu

stri

cto)

B

ty

peV

(pse

udof

ram

boid

s)

C

type

VI

(col

lom

orph

icpo

rous

pyri

te)

Dt

ype

VI

(bro

wn

collo

mor

phic

pyri

te)

E

type

VII

(mic

ro-g

eode

s)

Fty

peV

II(p

yrit

ein

terg

row

ths

inch

alco

pyri

te)

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion





marked area

1068








1069








00

05

10

15

20

25

30

6 4 5 65 0 6 55 6 6 0 6 6 5 6 7 0 S (at)

Type I

Type VI

00

05

10

15

20

25

30

31 0 31 5 32 0 32 5 33 0 33 5 Fe (at)

0

2

4

6

8

10

12

14

0 02 04 06 08 1 12 14 As (at)

Type I (ii)

(iii)

(i)

As

(at

)Fr

eque

ncy

As

(at

)

Type I

Type VI

a

b

c



1070







000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)






1071







1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080


TA

BL

E2

Che

mis

try

ofm

ediu

m-

toco

arse

-gra

ined

pyri

te(gt

20m m

)

A(n

=19

)B

(n=

21)

C(n

=39

)D

(n=

37)

E(n

=18

)F

(n=

107)

Wt

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Min

M

ax

Ave

sd

(1

s)

Au

000

016

003

004

000

006

003

002

000

016

003

003

000

005

002

001

000

005

002

001

000

010

002

002

Ag

000

006

001

001

000

003

001

001

000

009

002

002

000

005

001

001

000

147

018

035

000

017

002

002

S51

31

530

352

16

043

505

052

62

515

90

6449

39

536

152

10

078

508

753

83

527

20

7952

07

535

352

79

044

515

554

85

533

00

54Sb

000

003

001

001

000

011

002

002

000

019

003

004

000

004

001

001

000

004

001

001

000

006

001

001

Fe45

38

465

646

10

032

443

946

06

453

30

5344

51

467

546

05

049

443

946

41

456

60

6044

42

465

245

78

052

446

846

98

461

90

43C

o0

000

090

030

020

020

510

170

160

000

070

020

010

010

690

250

190

010

030

020

010

000

120

030

02N

i0

000

030

000

010

000

900

170

270

000

050

010

010

001

010

210

260

000

010

000

000

000

080

010

01C

u0

000

190

020

040

000

160

020

030

000

140

020

030

000

080

010

020

010

620

200

160

000

700

040

11Z

n0

000

300

030

070

000

020

010

010

000

040

010

010

000

040

010

010

000

040

010

010

000

390

020

04A

s0

242

270

990

661

033

382

270

600

282

761

280

800

003

380

831

180

000

100

020

020

000

230

040

05

Tot

al97

78

100

0999

32

063

985

110

067

996

20

5693

94

100

5299

33

110

989

610

063

997

30

3796

52

102

4099

03

153

982

010

248

999

70

80

At

Au

000

003

001

001

000

001

001

000

000

003

000

00

000

001

000

000

000

001

000

000

000

002

000

000

Ag

000

002

001

001

000

001

001

000

000

004

001

00

000

002

001

000

000

056

007

013

000

006

001

001

S65

44

665

065

93

029

646

966

26

654

50

4164

91

667

765

87

04

649

266

88

662

40

5866

32

668

366

58

016

658

367

36

667

00

32Sb

000

001

000

000

000

004

001

001

000

006

001

00

000

001

000

000

000

001

000

000

000

002

000

000

Fe33

07

338

533

45

020

322

133

94

330

20

4332

92

342

733

43

03

321

433

48

329

40

3132

54

335

133

15

021

323

834

08

331

90

32C

o0

000

060

020

010

010

350

110

110

000

040

010

00

000

460

170

130

010

020

010

000

000

080

010

01N

i0

000

020

000

010

000

620

120

180

000

040

000

00

000

700

150

180

000

010

000

000

000

050

010

01C

u0

000

130

010

030

000

110

010

020

000

090

010

00

000

050

010

010

010

400

130

100

000

440

020

07Z

n0

000

180

020

040

000

010

010

010

000

020

010

00

000

020

010

010

000

020

010

010

000

240

010

03A

s0

131

230

530

350

561

841

230

330

151

510

630

430

001

840

450

640

000

050

010

010

000

120

020

03

A

type

I(c

ores

)B

ty

peI

(pol

ygon

alba

nds)

C

ty

peI

(irr

egul

arba

nds)

D

ty

peII

E

ty

peII

IF

type

IV

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion

TA

BL

E3

Che

mis

try

of

ne-g

rain

edpy

rite

(lt20

m m)

A(n

=17

)B

(n=

9)C

(n=

18)

D(n

=33

)E

(n=

11)

F(n

=13

)W

tM

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)

Au

000

006

003

001

000

005

002

002

000

004

002

001

000

005

002

001

000

004

002

001

000

005

002

001

Ag

000

006

003

002

000

006

002

002

000

016

007

005

000

020

004

004

000

005

002

001

000

008

003

003

S52

46

537

953

23

036

486

053

09

518

61

4550

25

530

851

85

068

496

253

79

514

51

2151

75

534

652

68

057

517

553

66

530

60

53Sb

001

003

002

001

000

002

001

001

007

046

018

008

000

141

030

042

000

003

001

001

000

008

002

002

Fe44

53

465

245

91

043

411

145

43

441

91

4441

93

461

644

50

119

416

146

29

437

31

4245

68

466

246

27

024

452

746

33

457

30

37C

o0

010

050

020

010

040

100

070

020

010

040

020

010

000

040

020

010

010

050

030

010

010

030

020

01N

i0

000

020

000

010

010

110

040

030

000

140

050

050

000

010

000

000

000

040

010

010

000

080

020

03C

u0

000

050

020

010

000

020

000

010

000

940

250

270

001

260

190

270

010

390

130

110

001

320

570

39Z

n0

000

030

010

010

000

020

010

010

000

180

060

060

000

100

010

020

000

070

020

020

000

190

040

05A

s0

110

660

210

130

000

290

110

080

534

492

361

100

086

113

761

840

000

080

020

030

000

120

020

03

Tot

al97

44

100

6499

50

073

899

698

76

963

32

9198

20

100

4499

37

058

980

610

056

995

30

7197

95

999

299

22

058

980

610

092

995

30

93

At

Au

000

001

001

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

Ag

000

002

001

001

000

002

001

001

000

006

003

002

000

008

002

002

000

002

001

000

000

003

001

001

S66

45

672

066

75

019

667

367

28

670

20

1865

27

666

565

88

030

647

566

93

656

20

6466

03

667

766

35

026

660

566

97

665

80

29Sb

000

001

001

000

000

001

000

000

003

015

006

003

000

049

010

014

000

001

000

000

000

003

001

001

Fe32

64

332

833

05

017

325

233

03

327

90

1831

27

332

032

46

060

311

833

08

320

10

6133

09

337

933

47

025

326

133

89

329

50

35C

o0

000

030

010

010

020

070

050

020

010

030

010

010

000

020

010

010

000

030

020

010

000

020

010

01N

i0

000

010

000

000

010

080

030

020

000

100

030

040

000

010

000

000

000

030

010

010

000

050

010

02C

u0

000

030

010

010

000

010

000

000

000

610

160

170

000

830

130

180

010

250

080

070

000

830

360

25Z

n0

000

020

010

010

000

020

010

010

000

110

040

030

000

060

010

010

000

040

010

010

000

120

020

03A

s0

060

350

120

070

000

160

060

050

292

501

290

610

043

362

061

020

000

050

010

010

000

070

010

02

A

type

V(f

ram

boid

sse

nsu

stri

cto)

B

ty

peV

(pse

udof

ram

boid

s)

C

type

VI

(col

lom

orph

icpo

rous

pyri

te)

Dt

ype

VI

(bro

wn

collo

mor

phic

pyri

te)

E

type

VII

(mic

ro-g

eode

s)

Fty

peV

II(p

yrit

ein

terg

row

ths

inch

alco

pyri

te)

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion





marked area

1068








1069








00

05

10

15

20

25

30

6 4 5 65 0 6 55 6 6 0 6 6 5 6 7 0 S (at)

Type I

Type VI

00

05

10

15

20

25

30

31 0 31 5 32 0 32 5 33 0 33 5 Fe (at)

0

2

4

6

8

10

12

14

0 02 04 06 08 1 12 14 As (at)

Type I (ii)

(iii)

(i)

As

(at

)Fr

eque

ncy

As

(at

)

Type I

Type VI

a

b

c



1070







000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)






1071







1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080


TA

BL

E3

Che

mis

try

of

ne-g

rain

edpy

rite

(lt20

m m)

A(n

=17

)B

(n=

9)C

(n=

18)

D(n

=33

)E

(n=

11)

F(n

=13

)W

tM

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)M

in

Max

A

ves

d

(1s

)

Au

000

006

003

001

000

005

002

002

000

004

002

001

000

005

002

001

000

004

002

001

000

005

002

001

Ag

000

006

003

002

000

006

002

002

000

016

007

005

000

020

004

004

000

005

002

001

000

008

003

003

S52

46

537

953

23

036

486

053

09

518

61

4550

25

530

851

85

068

496

253

79

514

51

2151

75

534

652

68

057

517

553

66

530

60

53Sb

001

003

002

001

000

002

001

001

007

046

018

008

000

141

030

042

000

003

001

001

000

008

002

002

Fe44

53

465

245

91

043

411

145

43

441

91

4441

93

461

644

50

119

416

146

29

437

31

4245

68

466

246

27

024

452

746

33

457

30

37C

o0

010

050

020

010

040

100

070

020

010

040

020

010

000

040

020

010

010

050

030

010

010

030

020

01N

i0

000

020

000

010

010

110

040

030

000

140

050

050

000

010

000

000

000

040

010

010

000

080

020

03C

u0

000

050

020

010

000

020

000

010

000

940

250

270

001

260

190

270

010

390

130

110

001

320

570

39Z

n0

000

030

010

010

000

020

010

010

000

180

060

060

000

100

010

020

000

070

020

020

000

190

040

05A

s0

110

660

210

130

000

290

110

080

534

492

361

100

086

113

761

840

000

080

020

030

000

120

020

03

Tot

al97

44

100

6499

50

073

899

698

76

963

32

9198

20

100

4499

37

058

980

610

056

995

30

7197

95

999

299

22

058

980

610

092

995

30

93

At

Au

000

001

001

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

000

001

000

000

Ag

000

002

001

001

000

002

001

001

000

006

003

002

000

008

002

002

000

002

001

000

000

003

001

001

S66

45

672

066

75

019

667

367

28

670

20

1865

27

666

565

88

030

647

566

93

656

20

6466

03

667

766

35

026

660

566

97

665

80

29Sb

000

001

001

000

000

001

000

000

003

015

006

003

000

049

010

014

000

001

000

000

000

003

001

001

Fe32

64

332

833

05

017

325

233

03

327

90

1831

27

332

032

46

060

311

833

08

320

10

6133

09

337

933

47

025

326

133

89

329

50

35C

o0

000

030

010

010

020

070

050

020

010

030

010

010

000

020

010

010

000

030

020

010

000

020

010

01N

i0

000

010

000

000

010

080

030

020

000

100

030

040

000

010

000

000

000

030

010

010

000

050

010

02C

u0

000

030

010

010

000

010

000

000

000

610

160

170

000

830

130

180

010

250

080

070

000

830

360

25Z

n0

000

020

010

010

000

020

010

010

000

110

040

030

000

060

010

010

000

040

010

010

000

120

020

03A

s0

060

350

120

070

000

160

060

050

292

501

290

610

043

362

061

020

000

050

010

010

000

070

010

02

A

type

V(f

ram

boid

sse

nsu

stri

cto)

B

ty

peV

(pse

udof

ram

boid

s)

C

type

VI

(col

lom

orph

icpo

rous

pyri

te)

Dt

ype

VI

(bro

wn

collo

mor

phic

pyri

te)

E

type

VII

(mic

ro-g

eode

s)

Fty

peV

II(p

yrit

ein

terg

row

ths

inch

alco

pyri

te)

nnu

mbe

rof

anal

yses

M

in

min

imum

M

ax

max

imum

A

ve

aver

age

sd

st

anda

rdde

viat

ion





marked area

1068








1069








00

05

10

15

20

25

30

6 4 5 65 0 6 55 6 6 0 6 6 5 6 7 0 S (at)

Type I

Type VI

00

05

10

15

20

25

30

31 0 31 5 32 0 32 5 33 0 33 5 Fe (at)

0

2

4

6

8

10

12

14

0 02 04 06 08 1 12 14 As (at)

Type I (ii)

(iii)

(i)

As

(at

)Fr

eque

ncy

As

(at

)

Type I

Type VI

a

b

c



1070







000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)






1071







1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080






marked area

1068








1069








00

05

10

15

20

25

30

6 4 5 65 0 6 55 6 6 0 6 6 5 6 7 0 S (at)

Type I

Type VI

00

05

10

15

20

25

30

31 0 31 5 32 0 32 5 33 0 33 5 Fe (at)

0

2

4

6

8

10

12

14

0 02 04 06 08 1 12 14 As (at)

Type I (ii)

(iii)

(i)

As

(at

)Fr

eque

ncy

As

(at

)

Type I

Type VI

a

b

c



1070







000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)






1071







1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080








1069








00

05

10

15

20

25

30

6 4 5 65 0 6 55 6 6 0 6 6 5 6 7 0 S (at)

Type I

Type VI

00

05

10

15

20

25

30

31 0 31 5 32 0 32 5 33 0 33 5 Fe (at)

0

2

4

6

8

10

12

14

0 02 04 06 08 1 12 14 As (at)

Type I (ii)

(iii)

(i)

As

(at

)Fr

eque

ncy

As

(at

)

Type I

Type VI

a

b

c



1070







000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)






1071







1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080









00

05

10

15

20

25

30

6 4 5 65 0 6 55 6 6 0 6 6 5 6 7 0 S (at)

Type I

Type VI

00

05

10

15

20

25

30

31 0 31 5 32 0 32 5 33 0 33 5 Fe (at)

0

2

4

6

8

10

12

14

0 02 04 06 08 1 12 14 As (at)

Type I (ii)

(iii)

(i)

As

(at

)Fr

eque

ncy

As

(at

)

Type I

Type VI

a

b

c



1070







000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)






1071







1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080







000

010

020

030

040

050

060

000 010 020 030 040

Cu (at)

Ag

(at

)






1071







1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080








1072


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080


000

002

004

006

00 05 10 15 20 25 30 As (at)

645

650

655

660

665

00 05 10 15 20 25 30As (at)

000

020

040

060

080

00 05 10 15 20 25 30 As (at)

000

002

004

006

008

00 05 10 15 20 25 30As (at)

000

002

004

006

008

010

00 05 10 15 20 25 30 As (at)

000

010

020

030

040

00 05 10 15 20 25 30 As (at)

S (

at

)

Ag

(at

)

Cu

(at

)

Sb

(at

)

Zn

(at

)

Ni (

at

)

(a)

(b)



1073


















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080



















1074




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080




PRE-ORESTAGE

ORESTAGE

Pyrrhotite

Pyrite type IV


Pyrite type II



Pyrite type III

Pyrite type V

Pyrite type VI

Pyrite type VII

Gold precipitation






1075












1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080













1076





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080





Conclusions












St dev (1s) 151 165 241 018 013 113 54


1077




Acknowledgements


References





















1078





























1079







1080





Acknowledgements


References





















1078





























1079







1080





























1079







1080








1080


iron sulphides at the epithermal gold-copper deposit of ...hera.ugr.es/doi/14976353.pdf · au-cu...

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