orichalcum and related ancient alloys : origin, composition and manufacture : with special reference...

8/9/2019 Orichalcum and related ancient alloys : origin, composition and manufacture : with special reference to the coinage of the Roman Empire

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NUMISMATIC NOTES AND MONOGRAPHS

No. 151

ORICHALCUM AND

RELATED ANCIENT ALLOYS

Origin, Composition and Manufacture

with Special Reference to the

Coinage of the Roman Empire

By EARLE R. CALEY

Numn ATtc /

THE AMERICAN NUMISMATIC SOCIETY

NEW YORK

1964

This content downloaded from 83.85.134.3 on Wed, 03 Feb 2016 10:58:33 UTCAll use subject to JSTOR Terms and Conditions


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NUMISMATIC NOTES AND MONOGRAPHS

Number 151



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ALLRIGHTSRESERVED YTHEAMERICAN UMISMATICOCIETY

PRINTEDN GERMANYATJ.J.AUGUSTINGLÜCKSTADT



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Orichalcum and

Related Ancient Alloys

Origin, Composition and Manufacture

with Special Reference to theCoinage of the Roman Empire

By EARLE R. CALEY

THE AMERICAN NUMISMATIC SOCIETYNEW YORK

1964



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TABLE OF CONTENTS

I. INTRODUCTION III. THE EARLIESTCOPPER ALLOYS CONTAININGZINC . 3

III. THEORIGIN OFORICHALCUM I3IV. PREVIOUSANALYSESOFORICHALCUM COINS

OFTHEROMANEMPIRE 32V. NEWANALYSES OFORICHALCUM COINS 45

VI. ANALYSES OF ROMANCOINS COMPOSEDOF OTHERALLOYSCONTAININGZINC 69VII. COMPOSITION OFTHEORICHALCUMANDZINCBRONZE

SESTERTII ANDDUPONDII OF INDIVIDUALEMPERORS 77

VIII. MANUFACTURE OFORICHALCUM Ç2IX. VARIOUS ORICHALCUMOBJECTS

ANDSOME MODERNFORGERIES IO4

V



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I. INTRODUCTIONThe Greek wordôpeíxaÂKOçnd the correspondingLatin word

orichalcum,therwise pelledaurichalcum,esignateddifferent etalsor alloysat different imes,1ut this Latin word and its equivalentinmodern anguagesis now usedby numismatists odesignatea copperalloycontainingzinc which the Romansemployedin very late re-publicantimesand in imperialtimes as a material for coins. Somewriters n Roman numismaticsmplyorstate that orichalcumwasanalloyof fixed omposition,but this s not in accord with thefacts.Atno one time werethe proportionsof copperand zincheld exactlyconstant,and withpassageof time the proportionof zincgraduallydecreased while theproportions f tin and lead,whichin the begin-ningwerepresent n verysmallamountsasmere mpurities,ncreasedto such an extent that one or the other, or both, becameimportantcomponentsf the alloy.Hence,in a strict ense,the term orichalcumshould beunderstood to refernot to a singlealloybut to a class ofalloys that contained copper and zinc as principal components.ThoughRomanalloysof this class maybe calledbrass,they containlower proportionsof zinc than most varieties of modern brass.Orichalcums therefore convenientand distinctive term for desig-nating the particular kind of brass manufacturedby the Romans.Thecomplex copperalloys containingzinc, tin, and lead asprincipalcomponents,usedin the third centuryas materials forcoins,shouldpreferablybe calledzinc bronzesrather than orichalcumwhentheproportion f zinc is less than the proportionof tin, or when it is lessthan the proportionof tin and lead taken together.

It is not true, as hassometimesbeenstated, that orichalcum s theearliestknowncopper alloy containinginc.Examplesofmuch earlier1Rossignol,.P., Les métaux ansVantiquitiêParis, 863), p.205-331,ealsindetailwith heetymologyf thesewordsnd their ariousmeanings.hespellingrichalcumsdefinitelyobepreferredo aurichalcumForadditionaletymologicalnformationee:Diergart,., Zeitschriftür ngewandtehemieXIV

(1901), p. 1297-1301;bid.,XV

(1902),pp.761-763;bid.,XVI

(1903),pp.85-88.Disagreementith ome f theconclusionsfDiergart asexpress-edbyNeumann, .,Zeitschriftür ngewandtehemie,V(1902),p.511-516,1217-1218.

I



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2 Introductionalloysare now known.Thisstudy beginswith an inquiryas to theirplaceand time of origin,and a discussion ofthe difference etweenthesealloysand orichalcum as tocompositionand probablemethodof manufacture.

Thescantyinformation n the originand manufactureof orichal-cum given by ancient authors has been variouslyinterpreted bymodern writers. Often, isolatedstatementsof singleauthors have

beeninterpretedwithoutregard othebodyof nformations a whole,and without regard to certain chemical ormetallurgicalfacts. Itseemedworthwhile o bringtogether n one placeall the known an-cient technical information bout orichalcum,and to presentsomefresh nterpretations f its significance.

Many false or misleadingstatements about the compositionoforichalcum,and of orichalcumcoins, exist in the literature ofnumismatics. Some of thesestatements are the result of theinsufficient mount of chemical data availableat the time, others

the result of failure o make use ofthe data available,and stillothersthe result of failure o interpret hesedata correctly. his study con-tains a critical accountof all previousinvestigationsof the compo-sitionof orichalcumcoins,and presentsthe results of newand exactanalysesof twenty-five uch coins. Onthe basis of both the old andnew data thechangesin the compositionof orichalcumwith time ofmanufacture are traced in detail, and possiblereasons for thesechangesare suggested.Anattempt s made toestablishthe probabledate when orichalcumceased tobe manufactured for the Roman

coinage,and to determine heprobableduration of the periodwhenit was usedonlyas a reworked lloy. Thecompositionof ate sestertiiand dupondiistruck in zinc bronzesor other alloysis discussed,especiallyfrom he standpointofdeterminingwhen orichalcumeasedentirely o beemployedas a material for oins. Someconsiderationsgivento the compositionf smallorichalcumobjectsotherthan coins,andthe theory s advancedthat coins servedas theimmediate sourceof the metal for many of theseobjects.The possibilityof datingil-legibleorichalcumcoins and other orichalcumobjects from theirchemical

compositionsalso considered.

Finally,a

comparisons made

betweenhecompositionfgenuine richalcumnd that of fewmodernforgeries f ancientobjectscomposedofcopperalloyscontaining inc.



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II. THE EARLIEST COPPER ALLOYSCONTAINING ZINC

Althoughthe Romans wereundoubtedlythe first oemployalloysofcopperand zincforcoins,it is not true, as hassometimesbeenas-

serted, that this was the first use of such alloysfor any purpose.Centuries before their use by the Romans forcoins,copper alloyscontainingzincweresporadically producedand used for the manu-facture of a variety of objects.For a proper understandingof thedistinctivenature of orichalcum,t is necessaryto considerfirst hecompositionof these earlieralloys.

The comprehensiveresearches ofOtto and Witter and their co-workers how that copper alloys containingmoderateproportions fzinc wereoccasionally producedeven in the Early BronzeAge in

CentralEurope.Of the more than thirteen hundred metal objectsanalyzed bytheseinvestigators, hirty were found to containzinc asa componentof the alloy.2Nineof their analysesof such objectsarelisted n Table I. Theseanalysesweremadeby combinationof chemi-cal and spectrographicmethods.By reason of the stated degreeofaccuracyofmost of the determinations he results re here givenonlyto one decimalplace.The twenty-oneother objectswereanalyzedsolelyby spectrographicmethods,and thoughnumericalresultswerenot obtained for the coppercontent, the zinc content,or both, the

analysesshowedclearly that significant proportionsof zinc werepresent. t willbe seenthat onlyone ofthe objectslistedin Table Iwas found to containmorethan twentyper cent.A low to moderatezinccontent s characteristic fvery early alloysofcopperandzinc.Noexamplehas yet beenfound of such an alloyin which the proportionofzincreachesa third, the usual proportion n modernyellowbrass.It willalso be seenfromTable I that most of the objectscontainedtin in lowproportions, nd that a few of them containedsignificantproportions f ead. Thepresenceof tin or lead,or both together, n a

proportionnot much nferior o that of the zinc is frequent n ancient2Otto,H.,andWitter,W.,Handbuch erltestenorgeschichtlichenetallurgieinMitteleuropaLeipzig, 952),pp.210-21.3



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4 Orichalcum and Related Ancient Alloyscopperalloys containinginc,and sometimesheproportion f tin orlead,or both, considerablyexceedsthat of the zinc.

TABLE IANALYSESF EARLYBRONZE GEMETALBJECTSFCENTRALUROPE

CONTAININGINCAS A PRINCIPALOMPONENTFTHEALLOYObject Copper Zinc Tin Lead Other lements TotalNo. % % % % % %1 75.0 22.6 1.1 0.2 0.1 99.02 74.3 16.5 4.8 2.9 1.7 100.23 79.3 14.2 4.2 1.6 0.9 100.24 84.5 13.9 0.1 0.5 1.0 100.05 75.0 12.8 4.0 6.5 1.7 100.06 84.5 9.5 4.6 0.1 1.0 99.77 85.9 8.5 4.6 0.2 0.7 99.98 86.2 8.0 5.0 0.1 0.6 99.99 81.9 7.5 6.3 3.4 0.6 99.7

DescriptionsndNotes

1 Axwith ounded ead foundt Poppelwitz,reslaudistrict. tto-WitterAnalysisNo. 1355. The otherelementswere:nickel,0.02%;silver,0.01%;arsenic, .08%;bismuth, trace.AnalyzedbyH.Otto.

2.Daggerbladefound t Schraplau,Mansfeldake district.Otto-WitterAnalysisNo. 1358.The other lementswere:ron, .5%;nickel, trace;silver, .01%;arsenic, .01%;antimony, .01%;bismuth, .07%.Ana-lyzed byJ. Winkler.

3.Flangedcelt found t Bennewitz,aal district.Otto-WitterAnalysisNo. 1349.Theother lementswere:iron,0.7%;nickel, trace; silver,0.04%;arsenic, .1%;antimony, .04%;bismuth, .05%. AnalyzedbyJ. Winkler.4. Rodfound t Zerbst. Otto-Witter nalysisNo. 1366.The other ele-mentswere:ron, .2%;nickel, .04%;arsenic,.5%;antimony, .3%;sulfur, trace.Analyzedby H. Otto.

5. Heeledcelt fromFinsterwalde.Otto-WitterAnalysisNo.1352.Theother lementswere:ron, .3%;silver, .08%;arsenic,.1%;antimony,0.1%;bismuth, .08%. Analyzedby J. Winkler.

6.Bar found n the Rhine betweenIngelheimernd Peteraue.Otto-WitterAnalysisNo.1359.The other lementswere iron, .03%; nickel,0.05%;cobalt,a trace;silver, .05%;arsenic, .1%;bismuth, trace;sulfur, .5%.Analyzedby H. Otto.

7.Barfound t RettbergAue nearMainz. Otto-WitternalysisNo. 1361.Theotherelementswere:iron,0.2%;nickel,0.06%;cobalt,a trace;silver, .05%;gold, trace;sulfur, .3%.AnalyzedbyH.Otto.



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Earliest Copper Alloys ContainingZinc 58.Bar found n the Rhine betweenIngelheimernd Peteraue. Otto-

WitterAnalysisNo. 1360. Theother lementswere: ron, .2%;nickel,a trace; cobalt,a trace; silver, .5%;arsenic, .1%;bismuth, trace;sulfur, .3%.AnalyzedbyH.Otto.

9.Flangedcelt found t Bennewitz,aal district.Otto-Witter nalysisNo.1350. Theother lementswere: ron, .4%;nickel, trace;silver,0.04%;arsenic, .08%; antimony, .03%;bismuth, .08%. Analyzedby J. Winkler.

Analysesof various otherprehistoric bjects composedof copperalloyscontainingzinc are listed in Table II. At least someof theseobjectsare later in date than those listedin Table I.No.1 wasanal-yzed byMoss3 nthe course ofhisinvestigationsf the residues eft nmetallurgicalcrucibles usedby the crannogdwellers of Ireland. Inview of the smallweightof metal available foranalysis,his resultswerecorrectly xpressedonlyto the first ecimalplace.ThestyleofNo. 2, analyzed byChurch,4 learly indicateda pre-Romandate.Thoughhe expressedhis results to two decimalplaces, theyare here

givenonly to one in view of his high summationand his failuretodetermine ertain mpuritieswhichmusthavebeenpresent.No.3wasanalyzed by Fellenberg.5This investigatorfound significantpro-portionsof zincin severalother objects,but these appearto belongin the Romanperiod,though a fewmay be earlier. No.4, analyzedby Helm,6s notable ascontainingan unusuallyhigh proportionofzinc for n ancientobject.The presenceof so much bismuth is alsoveryunusual.Thoughtherehasbeen somecontroversys to the dateof this object,the mostprobabledate appearsto be the middle of the

LaTèneperiod.No.5,alsoanalyzed byHelm,isbelieved tobelongtothe earlierpart of this sameperiod.Nos.6 to 9,inclusive,analyzedbyBibra,7all came frommoundgravesin the provinceof Hannover,Germany.Theirexactageis uncertain,thoughthey areprobablyallmuchearlierthan the beginning f the ChristianEra.3Moss,R. J.,Proceedingsf heRoyalrishAcademyXXXVII C(1924-1927),p. 186.4Church,.H.,Journal f he hemicalocietyXVIII(1865), .216.5Fellenberg,. R.von,MitteilungenerNatur orehendenesellschaftn Bern(1863), . 54.6Helm,O.,Zeitschriftür thnologieXXVII(180*;), p. 7-8.7Bibra, . von,DieBronzen ndKupferlegierungener lten nd ltestenölker(Erlangen,869),pp.122-123.



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6 Orichalcum and Related AncientAlloysTABLE II

ANALYSES F PREHISTORICETALBJECTSF VARIOUS ATESFROM HEBRITISH SLES ANDNORTHERNUROPEONTAININGINCASAPRINCIPAL

COMPONENTFTHEALLOYObject Copper Zinc Tin Lead OtherMetals Total

No. % % % % % %1 78.8 15.5 3.1 0.9 1.9 100.22 88.2 9.1 3.6 - - 100.93 80.30 16.31 2.85 0.16 0.38 100.004 63.86 30.62 1.13 0.18 4.21 100.005 70.71 27.30 1.04 trace trace 99.056 75.70 19.05 3.14 0.88 1.86 99.637 82.85 12.87 3.02 0.93 0.33 100.008 87.19 9.70 1.01 0.70 1.40 100.009 87.05 5.00 7.86 trace 0.09 100.00

DescriptionsndNotes1. Smallbead from lagin a cruciblefound n CountyGalway,reland.

The othermetalswere:ron, .9%;nickel, .0%.2. Massivebracelet ound tAboyne,cotland.Asimilar racelet rom hesamelocalitywas foundto contain:copper,86.5%;zinc,1.4%;tin,

6.8%;lead,4.4%.The zincn thisonemaybe considered o bepresentas amere mpurity.

3. Spiralfrom n IronAge graveat Cammin,Germany. he metalwasfound o contain .38%iron.

4. Spoonfrom he ancientburialgroundt Rondsen,Germany.he othermetalswere: ron, .23%;bismuth, .98%.

5.Fibulafrom heancientburialgroundt Rondsen,Germany. traceofironwas found.Thelowsummationf thisanalysismaybedue to the

presencef corrosion

roductsn the

sampletakenfor

nalysis.6.Fragmentf a largevessel. The othermetalswere: ron, .93%;nickel,0.93%;antimony, trace.

7.Fragmentf vessel.Theothermetalswereiron, .33%; nickel, traceantimony, trace.

8.Fragmentf fibula. he othermetalswere iron, .10%nickel, .30%.9.Small ornamentalhieldwithring.The othermetalswere: ron, trace;

nickel, .09%;antimony, trace.The earliestknown metalobjectsof the Mediterraneanregionthat

containsignificant roportionsof zinc were found at Gezerin Pal-

estine.8n

most ofthese the zinc content s lessthan four

percent,and

8Macalister,. A.S.,TheExcavationsfGezerLondon,912),Vol. I, pp.265,293,303.Theanalysesweremadeby J. E. Purvis.



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Earliest Copper Alloys Containing Zinc 7could beregardedas a mere accidentalimpurity.However,one oftheobjectsfrom this site was found to contain 23.40per cent of zinc,alongwith 10.17Per cen* °f tin and 66.40per cent of copper.Thisobject,the metal of whichmaybe termeda zincbronze,is believedto belongto the periodknownas SemiticIII (1400-1000b.c.).Thisis by far the earliestknownobjectfrom he Mediterraneanregion nwhichzinc is clearlypresentas a principal componentof the alloy.Moreover,no other object from this regiondated prior to the firstcenturyb.c. hasyetbeen foundn whichzinc ispresentwithcopperasa principalcomponentof an alloy.Manybronzeobjectsfrom he in-terveningperiodof abouta thousandyearshave beenanalyzed,butzinc,whenpresentat all, has beenfound to occurin theseas an ac-cidental mpurity n proportionseldomexceedinga fewtenthsofoneper cent. Bibra9found2.30per cent of zinc in a Macedonianbronzecoin and 3.72per cent in a bronze coin ofSyracuse,but these areunusually highproportions orGreek bronze ofanykind. Thehighestproportionof zinc found n any Greek bronze coinanalyzed bytheauthor and hisco-workerswas 0.20per cent,and ofa groupofeightysuchcoins therewerefifty n which zincwas notdetected at all.10

Theonlymetalobjectsthat maybe classified s Greekandinwhichzinc has been found to be a principalcomponentof the alloywerefound t or near Greek colonies orsettlements n the Black Sea.Onlyfour objectsof this kind are known. Allwereanalyzedby Bibra.11The results of his analysesare listedin Table III. Thereason fortheperfect ummations ofall these analysesis that Bibra customarily

determined opper by difference,.e., by subtractingthe total of allother determinationsfrom 100.00per cent in order to find the per-centageof copper.On the basis ofarchaeologicalevidenceall theseobjectsare of ate b.c. date.Nos.1and2 arebelieved tobelongn thefirst entury b.c. Nos.3 and 4 are dated beforethe beginningof theChristianEra, and probablyalso belongin the first century b.c.However,there s somepossibility hat the actual date ofmanufactureof some orall of these objectsmay be a little earlier than the first

9Bibra, . von,op.

it.,pp. 86-87.10Caley, . R., TheCompositionfAncient reekronze oins Philadelphia,1939), .151-11Bibra, . von,op.cit., p.98-99,102-103.



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8 Orichalcum and RelatedAncient Alloyscentury. t will be seen that small proportionsof tin are present nNos. i and 2 alongwith the zinc. In this respecttheir compositionresembles that of some of the prehistoricobjectslisted in Tables Iand II. But thecompositionof Nos.3 and 4 doesnot, sincethey arefree from in and containvery little lead. In beingcomposedessen-tiallyofcopperand zincalone,the alloysof whichtheseobjectsweremaderesemblethe early type of orichalcum usedby the Romans for

coinage. Theydiffer, owever, n containingmuch lowerproportionsofzinc.

TABLEIIIANALYSESF PRE-ROMANETALBJECTSROMITESON THENORTHERNSIDEOFTHE BLACK EACONTAININGINCASAPRINCIPALOMPONENTF

THEALLOYObject Copper Zinc Tin Lead OtherMetals TotalNo % % % % % %1 82.76 13.31 3.40 0.19 0.34 100.002 84.87 10.12 4.36 0.21 0.44 100.003 91.00 9.00 none trace traces 100.004 90.59 8.10 none trace 1.31 100.00

Descriptionsnd Notes1.Fishhookfrom Greekgraveon the Crimea.Theothermetals were:

iron, trace;nickel, .34%.2. Fishhookfrom Greekgraveon the Crimea.Theothermetals were:

iron, trace; nickel, .44%;cobalt,a trace.3.Ringmade offine wistedwire from heruinsof ancientTanaïs. The

othermetalswere:ron, trace; nickel, trace;antimony,

trace.4. Wirefrom grave n the vicinity f ancientOlbia. The othermetalswere: ron,1.31%; antimony,trace.

The first knownuse of alloysof copperand zinc forcoinageoc-curredin the late Roman Republicanperiod, apparentlyjust afterthe middle ofthe first enturyb.c.This conclusions basedchiefly nthe four analyseslisted in Table IV. Theseanalyseswerepublishedby Bahrfeldt,12ho doesnot name the analyst.Thefigures iven byBahrfeldtndicatethat onlycopperand zinc weredetermined, houghthe deficienciesn the summationsof three of the

analysesshow that

certain mpurities, uch as tin, ead, or iron,werealsopresent.How-12Bahrfeldt, .,NumismatischeeitschriftXXVII(1905),p. 42.



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Earliest Copper Alloys ContainingZinc 9ever,since each of thesedeficiencies mounts to little more than oneper cent, the individual proportionsof the various other metalspresent s impuritiesn thesecoinsmust have been small. These fouranalysesare clearly very important from the standpointof numis-matic history, for they establish the time of the introduction oforichalcum s acoinagemetal.Theyare the onlyquantitativechemi-cal analysesthat have been made of orichalcum coinsissued before

the reignofAugustus.However,one coin ofthe late RomanRepubli-canperiodhasbeen shownby a spectrographicest to consistchieflyofcopperandzinc,the proportion f zinc beingestimated to bein therange 10-15%.This coin wasissuedin Macedoniain 44b.c.,possiblyby the quaestor,Acilius.13Slightly ater coins,issuedby Sosius atZacynthusin 37 b.c., are said to be composedof orichalcum,nd ithas beensuggestedhata few ther moneyers f the very ateRepubli-canperiodmayalsohaveissued coins inorichalcum,houghdecisiveevidence based on chemical orspectrographictests appears to be

lacking.14n the other hand,such tests haveclearly hown that a fewtypesof ateRepublicanorearly mperialcoins, rroneouslylassedasorichalcumcoins because of theircolor,are in fact composedof ordi-nary tin bronze or leadedtin bronze.

TABLEIVANALYSES FORICHALCUMOINS FTHEROMAN EPUBLIC

Coin Copper Zinc TotalNo % % %

1 71.11 28.88 99.992 71.10 27.60 98.703 78.60 20.30 98.904 83.84 15.00 98.84

Identifications1,2. Coins ofC.Clovius,45 B.c.3,4. Coinsof Q. Oppius,32-31B.c.

Grant From mperium o AuctoritasCambridge, 946,pp.11,63)isof the opinionhat the coins of C. Cloviuswere ssuedn CisalpineGaul,probablyt its capital,Mediolanum,nd that those of Q.Oppiuswere

13Grant,M.,FrommperiumoAuctoritasCambridge,946),pp.17,18, 89,493-14Grant,M.,op.cit., p. 40,89.



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io Orichalcumand Related AncientAlloysissuedin Syria, probablyat Antiochand perhapsalsoat ApameaorLaodicea.

Thecopper alloyscontaininginc,which ppearedbefore richalcumwasregularlyused forcoinageby the Romans,differ n various re-spectsfrom his Roman alloy.Their zinc content varies overa widerange, n the prehistoric lloys especially,as is shownby the data inTablesI and II. Moreover,s is shown n Table V, these earlieralloys

containhigherproportions f metals other than copperand zinc.Es-peciallysignificant re the higherproportions f tin and lead,whichare presentonlyin slight proportion s impurities n the orichalcumfirst sed asa coinagemetalby the Romans. Anothermportantdif-ferences the sporadicoccurrencen respectboth to placeand timeofobjectscomposedof these earlier alloys,and their great scarcityascomparedto objectsof imilar ge composedoftin bronze. n contrast,orichalcumcoinswereregularlyproducedin a few ocalitiesin enor-mous numbersfor nearly two centuriesbeginningwith the time of

Augustus.All these differencesndicatethat the earlier alloyswereproduced accidentallyand that orichalcum wasintentionallymanu-factured.Apossible exception maybe someof the copper-zincalloysproducedn the vicinityof the BlackSea,as seemsto be indicatedbythe compositionof the objectsnumbered3 and4 in Table III.

TABLE VTOTAL ROPORTIONF ELEMENTS THER

THANOPPERNDZINCGroup KindandSource Sourceof Other lements%

No. ofObjects Data MaximumAverageI. EarlyBronzeAge, Table I 12.2 6.5CentralEurope

II. Prehistoric, Table II 8.0 4.5British slesandNorthern urope

III. Greek,Northern Table III 5.0 2.6BlackSea Coast

IV. Orichalcumoins, TableIV 1.3 0.9RomanRepublic

V. Orichalcumoins, Table XVII 1.2 1.0RomanEmpire,B.c. Period



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Earliest Copper Alloys ContainingZinc 11These differenceslso indicate that the prehistoricalloys were

produced bya somewhatdifferent rocessthan the one used for themanufactureof orichalcum.Theycouldnot have beenmadeby thedirect alloyingof copperand zinc,as in modernpractice,since me-talliczinc couldnot have beenproducedin the opencrucibles,crudefurnaces, r primitivehearths used for melting n prehistoric imes.Themetallurgy f zinc ispeculiarin that the temperatures equiredto reduce its minerals or oresto metal with carbon are close totheboilingpointof the metal itself, o that it vaporizes awayas soonasitis formedunless some meansis employedto condense or otherwisetrap t. Furthermore, nlessair isexcluded,thevaporizedmetalburnsimmediatelyto its oxide at these elevatedtemperatures.Nor couldtheseearlieralloyshave beenproduced bythe reductionof a mixtureofcopperand zincores,ora singleorecontainingbothcopperand zincminerals.Bronzemaybe easily produced byan analogousprocessnprimitive pparatusfrom mixture ofcopperand tin ores,but brass

cannotbeproduced bythisgeneralmethodformaking alloysbecausea temperaturehigh enoughto reduce the copperand zinc ores wouldalso behigh enoughto vaporizeand oxidizepracticallyall the zincbefore t could alloywithany copperformedby reduction.However,undercertain conditionscoppercontaininga lowpercentageof zincmaysometimeshave beenaccidentallymade.If a heterogeneousmix-ture of the two ores and charcoal wereunevenlyheatedin a cruciblesomecopper mighthave been formedby reductionbefore ll the zincorewas reduced. Some of the zinc from he reductionof the remaining

zincoremightthen have beentrapped by the metalliccopperbeforeit could vaporize.This is onewayto account for the presenceof thelowproportions f zincthat not infrequently ccur as animpurity nprehistoric opper. More than a fewper cent could not have beenintroduced nto copper bythis means.

The formation f a copper-zinc lloyby cementation ppearsto bethe onlywayby which the prehistoric lloyswereproduced.In thismethod, s it was carriedout in earlymoderntimes, hinbars or smallpiecesof copperare buried in a mixture of zinc ore and charcoal

containedin a crucible. Onheatingthe crucible and its chargeto asufficiently igh temperature ome of the zinc formed y reduction svaporizedand lost but most of t is trappedin the hot surface of the2



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12 Orichalcum and Related Ancient Alloyscopperto form copper-zinc alloy. Bythe subsequentfusion of themetal, and by stirring, homogeneous alloyis produced.This wasthe methodemployedformakingbrassin earlymoderntimes,and insomeplacesit was used long after metallic zinc becamegenerallyavailableformakingbrassby directalloying.n prehistoric imes theproductionof a copper-zinc alloyin this waywas in all probabilitythe accidental result of one of the processesthen commonlyused for

the manufacture f bronze. In this processcrudecopperobtainedbythe reductionof a copperorewithcharcoal,or evenwood,washeatedwitha mixture f tin ore and fuel.16 hetin formed y the reductionofthe tin ore alloyedwith the copper,and by fusion and stirringhomogeneous alloywas produced. Probablythe prehistoricbronzemakers at the periodwhenthisprocesswas in use didnot evenrecog-nize that tin was formed s a separatemetal,but believed rather hatthe processwas onein whichthe crudecopperwasimprovedn quali-ty by being treated in this way. In the early developmentof the

processvarious mineralsand oreswere n all probabilitytried beforetin ore, n the form f cassiterite or tinstone,wasfound to be the onethat gavethe best results. Even after this became well known it isprobablethat other ores were tried as substitutesor extenderswhentin ore became unavailable orscarce.Moreover,the superficialre-semblance of some other ores totin ore may have caused them tobe usedunintentionally.16hus it came about that at various placesand timessome of theeasilyreducedores ofzinc and lead weresome-times substituted for tin ore to a greater or lesser extent with the

resultthat the alloyobtainedby this processcontainedtin, zinc,andleadinvarious combinationsnd in a widerangeofrandomproportions.AsshownnTablesI andII this is justwhattheanalysesshow forpre-historic opperalloysthat containzinc asa component.Moreover,hevariety nd proportions f thevarious minor omponentsr mpuritiesin thesealloysndicateclearlythe use ofmanydifferent inds of ores.15Forbes,R. J., Metallurgyn AntiquityLeiden,950),p. 250.16 rehistoric inersndmetallurgistsrobablyxperiencedreat ifficultyndistinguishinglearlyertain f thedarkcoloredresfrom ach other. or ex-

ample,instonendzincblende ometimesesembleachother loselyn both

color nd luster.No suchdifficultyasexperienced,owever,nrecognizingtheoxidized resf opperwhichhey sedfor ronzemanufactureince hesehave avery triking lueorgreen olor.



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III. THEORIGIN OF ORICHALCUM

Anyinquiry nto the origin nd technology f orichalcummust n-volve the questionof whether ancient metallurgistsever producedmetalliczinc,andif so,whether hey recognizedt as a distinctmetal.Thoughthe discoveryof ancient objects composedof zinc has atvarioustimes been reported by archaeologists,the stated identifi-cationaszincappearsoften o havedependedonphysicalappearancerather than on chemicalanalysis.The earliest suchreport was byGrignon,17hoexamineda pieceofmetal found at a Roman sitebe-tween St. Dizierand Joinville n France and concluded that itwasworkedzinc. But hisreasons forthis identification re vague,andprobablyno reliable chemicaltests weremade,if indeedthey could

have beenmade at such anearlydate. Salzman18eported hat certainbraceletsfound t the ancientnecropolisofKameiroson the IslandofRhodeswere formed of hollow silverfilledwith zinc. He does notstate that chemical tests were made,and the possibilityexists thathe mayhave based hisidentification n the grey crystalline ppear-ance ofinternallycorroded silver. Moser19eportedthat an ancientbell-shaped objectcovered with a mottledbluish-grey nd yellow-ish-brown atina, found n excavations at CastelvenerenearTrieste,wascomposedof zinc or a zinc-antimony lloy.He alsofailsto state

that any chemicaltests weremade,and the uncertainty f his identi-fication eemsto indicate that he depended solelyon the appearanceofthepatina.Afewothervagueoruncertain dentifications avebeenreported.

Helm20wasthe first o show clearly by chemicalanalysisthat anancientmetal objectwascomposedmostlyof zinc.Thisobject,de-scribedby him as beinga prehistoricDacianidol, is stated to have17Grignon,. C'Bulletin es ouilles*ne illeomaineBar-le-Duc,774), .1118Salzman,A.,RevuerchéologiqueIV(1861),p. 472.19Moser,. K.,

Mitteilungener

nthropologischenesellschaftnWien,XXXV

(1905),Sitzungsberichte,. 52.20Helm,O.,VerhandlungenerBerlineresellschaftürAnthropologieEthnolo-gieundUrgeschichte1895), .621.** 13



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14 Orichalcumand Related AncientAlloysbeen foundat Tordosin Transylvania.It was coveredwith a bluish-grey ayer of corrosionproducts.Ontestingthe objectwitha file hemetal was seen tobe white. Helmat first houghtthat the metalwasantimony,but he found on analysisthat a sampleof it had thefollowingomposition

Metal %Zinc 87.52

Lead 11.41Iron 1.07On the basis of these results Helm concludedthat the metal wascrude zinc.He senta sampleto the famousanthropologist,Virchow,who,because ofthe apparenthistoricalimportanceof the identifi-cation,had the sampleexaminedindependentlyby another chemist.Thischemistfoundthat the samplewas nota uniform lloy, as theresults obtainedby Helm wouldseem toindicate,but was composedoftwolayerssolderedor weldedtogether, heonebeingzincand the

other lead. However,the essentialfact was confirmed hat metalliczinc was theprincipalcomponent.n his criticisms f the conclusionsof Helm,Virchow21ointedout that the objecthad not been foundunderthe controlled onditionsofarchaeologicalexcavation,but wasevidently surfacefind, nd that thereforets real placeoforigin ndits actual date were unknown.He evenquestionedthe authenticityof the object, though Helm had previouslystated that fraud orforgerywasout of the question.Virchow concludedthat there wasnoevidence toshowthat it was a prehistoricDacianobject,thoughhe

admittedthat it could havebeenmade inDaciaduringthe Romanperiod.In a later paper, Helm22announcedthat he had identifiedanotherancientDacianobjectasbeing composedmostlyofzinc.Thisobject,from privatecollectionofantiquities,wasanelongatedumpofcorrodedmetalwithan iron wireimbeddedin it, which seemedtoindicatethat it mighthave beenthe clapperofa bell.Unfortunately,the provenanceof this objectwasalso uncertain.

Theonlyancientspecimenof definitely nownprovenanceidenti-fiedbeyonddoubt as metalliczinc wasfoundin the course of the

21Virchow, .,Zeitschriftür thnologieXXVIII(1896),p.338-339.22Helm,O.,Correspondes-lattderdeutschenesellschaftürAnthropologieEthnologiendUrgeschichteXXX(1899),p. 100.



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Origin of Orichalcum 15excavationof the Agoraat Athens.23As toprovenance,the discover-er, Dr. ArthurW. Parsons,reported as follows: The fragmentofzinc was found n SectionOA onMay13,1939,at the base of the cliffon the north lopeof the Acropolis,t a pointabout7.0meters ast ofthe ancient fountainhouse,the Klepsydra,and directlybelowthecavesanctuaryof Pan. Thepottery nd coins with which t wasfoundwerechiefly f the 4th and3rdcenturiesb.c.; therewasnothing ater

than the 2nd centuryb.c. It maybe regardedas certainthat the zincgot there no later.The fragmentwas in the form of a pieceof flat sheet, roughly

rectangular n shape,and measuringabout 65by 40mm.Most of itwas0.50to 0.55mm.thick,but it was very thin at the edges.A fewpits penetratedright through the piece.The fragmentwas at firstsupposedto be composedof ead,and it was not until after t hasbeendrasticallycleaned to seeif it bore an inscriptionthat qualitativetests were made that revealed that it was composedmostlyof zinc.

Half of the fragmentwas sent to the ResearchLaboratoryof theNewJerseyZincCompanyfor quantitative spectrographicnalysis.The followingresults were reported for the principalmetallicim-puritiespresent

Metal %Lead 1.3Cadmium 0.060Iron 0.016Copper 0.0055

Smallerproportionsor traces of magnesium,manganese, antimony,tin, and silver were also found. Thisis a greatervarietyof mpuritiesthan spresent nmodern inc,but the proportionof lead islessthanin somegradesof modernzinc,and the proportions f cadmium andiron are no higher.

Ametallographicxaminationof a sampleof the fragment howedthat the metal had the structure f slightlyworkedzinc,but not thestructure f heetzincformedbythe modern method of rolling.Metalofthestructure bserved could have beenformed y hammering ut a

lumpof cast zinc not morethan ten times thicker hanthe fragment.23Farnsworth,.,Smith, . S.,andRodda,J. L.,Hesperia,upplementIII(1949),P-126-129.



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i6 Orichalcumand Related Ancient AlloysThepuzzlingfeature about this fragment s its survivalin sucha

locationfor o longa period. Concerninghis,Farnsworth, mith, andRoddastate: Whileit is hard to believethat a sampleof a reactivemetal ikezincwould notdisappear bycorrosionn much essthan2000years n a locationdamp enoughto cause severe corrosion fadjacentbronzecoins,the spectrographicnd metallographic nalyses agreeinshowingthat the presentsampleis unlike modern zinc in both com-

positionand method ofworking, nd supportthe archaeologicalevi-dence of ts antiquity/' However,they suggestthat this fragment fzinc had a protectivesurfacelayer or a coatingthat retarded itscorrosion.Unfortunately, the opportunity of demonstratingthepresenceof such a layeror coatingand ofascertainingts nature waslostbecause thefragmentwas sodrasticallycleaned before tsuniquenature was recognized.

Becauseof the chemicalreactivityof the metal,the great scarcityofancientzincobjects mightconceivablybe ascribed to theirgeneral

disappearance throughorrosion.However,f metallic zincreallyhadbeen abundant and in generaluse in Greek and Romantimes, itseemsikelythat manyzincobjects,particularly hose of thickmetal,would have survived inprotectedlocations.Perhapsthe strongestargumentagainst the abundanceor generaluse of metalliczinc inclassicalantiquity s the moderatelyow zinc contentof copper-zincalloysthat have survived fromthat period.In not one of the con-siderable numberof objectscomposedof such alloysthat have beenanalyzeddoes the zinccontent reach forty per cent, and generally

it is much lower. Sucha lowlimit to the zinc content of these alloysindicatesthat they were madeby a cementationprocessand not bythe direct alloyingof the two metals.If metallic zinc hadbeengener-ally availablefor alloyingwith copper,it is highlyprobable thatancientmetallurgistswould have manufacturedomealloysof higherzinc content and that someobjects composedof such alloyswouldhavesurvived.

In general,the archaeologicalevidence shows thatmetalliczincwasextremely carcein classicalantiquity. Probablyit was onlyac-

cidentallyand

occasionallymade in

verysmall amounts in a few

placesin the courseof certain metallurgical operations,probablyinmuch the same way as zinc was first ccidentallyisolatedin small



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Origin of Orichalcum 17amountsn certainmetallurgicalperationsnEuropeinearlymoderntimes.AccordingoRickard24 he metal was notrecognizednmodernEuropeuntil 1509when t was detected n the form f beads ordropsin slagat the silver-smelting orks on the Rammelsbergn Germany.A little later it was found in small amountsas metal condensedincracks or crevicesn the walls ofcertainsmeltingfurnaces.25n viewof the compositionof the primary re workedfor ilver n the famous

Greekminingdistrict f Laurionin ancienttimes, t seemsvery ikelythat zinc was sometimessolatedn theslagorsmelting urnacesuringthe long periodwhen thesemines wereworked.ThisLaurionoreis amixtureof the sulfides f ron, ead, and zinc.26 he silver s containedin the lead sulfidegalena)and the ancient Greeks solatedthis fromthe mixture of sulfides by a sortingand washing processbefore theactualsmelting.27owever,it is likelythat this separationwasoftenimperfect nd that somezincsulfide sphalerite)was includedin therefined re smelted for silver. In fact, there s evidencefor this in a

statementby Pliny28whosaysthat a productcalled lauriotis evident-ly a formof zinc oxide named afterthe miningdistrict at Laurion,was formed n silver furnaces.In another place29he remarksthatcadmeaunquestionablyoccursin furnaces used for silver smelting.Thisterm, whenappliedto an artificialproduct,undoubtedlydesig-nated zinc oxide formed on the walls ofsmeltingfurnaces.30romother remarksmadeby Pliny31t may be inferred hat the sizeanddesignofthese furnaceswere such that considerablequantitiesofzincoxideand otheruseful volatileproductscollected on theirwalls and

in their chambers.This makesit seem evenmorelikelythat smallamounts of metallic zinc sometimesondensed ncracksor crevicesofthe walls of thesefurnaces.24Rickard,. A.,Manand MetalsNewYork,19^2),Vol.I, p. 158.25Lohneys,.E.,Berichtom ergwerckenZellerfeldt,617), p. 83-84.26Marinos,.P., andPetrascheck,.E., LaurionAthens, 956),pp.232-233.27 omeof the ancientortingndwashingasins ndtableshaveremainedessentiallyntact t Laurion pto thepresentime.28NaturalHistoryBookXXXIV,sec.132.29Natural

HistoryBook

XXXIV,sec. 100.

30Bailey,K.C.,TheElderPliny*ChaptersnChemicalubjectsLondon,929-1932),Part I, pp.166-167.31NaturalHistoryBookXXXIV,sees. 11-102.



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i8 Orichalcum and Related AncientAlloysThegreat scarcityofmetalliczincin classicalantiquity s alsoin-

dicatedby the scarcityof information bout it in the works of thewriters f that period.Onlytwopassages,bothby Greekauthors,canbe interpreted s referring othe isolationofzinc,and one of these sapparentlya fairly losequotationof the other. Theoriginal passageoccurred n the Philippicaof Theopompus,a historianof the fourthcentury b.c., but its occurrence n this work is knownto us only

through uotations of t or references o it in the works of much laterwriters. t is, for xample, quoted byStephenofByzantium,a writerof the sixth century A.D.in one of the surviving fragments f hisGeographicalLexicon32This writer also indicates that an earlierquotationof t isgivenby Straboin hisGeographywhich was writtenabout the beginningof the Christian Era. Strabo, himself,does notstate or even hint that he quotedfrom heopompus,but a comparisonof the two quotationsclearlyshows that he did. The quotationbyStrabo33may be closer to the original,for he was much nearer to

Theopompusin time of writing nd probablyusedan earliermanu-scriptof the Philippicathan was availableto StephenofByzantium.The text of the pertinentpart of the passagein Strabo isas followsson 8èAtóosspi Tà vAv8eipaçKaiópevoçíSrjpoç yvetou* tra iíetòyfļs ivòçKa|iivev0eiçaroaráLeiyeuSápyupov,f' TTpocrAaßouaac(KkòvTÒKOÀÓ1JEVOVVETOUpāļJOl,TIVSÇpEÍXaÂKOVOÀOVOT

Althoughthe languageof this text is fairly lear,its meaningfromthe metallurgicalstandpoint is rather obscure,and chieflyfor thisreasonit has been translatedand interpreted n variousways.Some

scholarshave evenalteredthe standard text of the passagein ordertoimprove ts sense,but without soundjustification.Thefollowings aclosetranslation: There is a stone near Andeira whichyieldsironwhen burnt. Afterbeingtreated in a furnacewith a certainearth ityieldsdropsof false silver.This,addedto copper,forms heso-calledmixture,which somecalloreichalkos.

This passageis obviouslya sketchy account of a metallurgicalprocess bywhicha copperalloycalledoreichalkoswasproduced.At

32 or the ext f hisuotation

ee:Grenfell,. P., andHunt,A.S.,H ellenicaOxyrhynchiaumTheopompitCratippiragmentisOxford,909),hilippicaBookXIII,sec.109.83GeographyBookXIII,sec.56.



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Origin of Orichalcum 19the time of Strabo there seemsto be no questionthat the GreekèpeíxaÀKoças the equivalentof the Latin orichalcumnd that bothmeantan alloyofcopperand zinc.Henceit would seem evidentthatthe Greek yevSápyupoç (falsesilver)must be metallic zinc. Mostscholarshave concluded that this wasthe process,or one of theprocesses,n use forthe productionof orichalcumaroundthe begin-ning of the Christian Era. What they have overlooked,however, s

the strong probabilitythat Strabo has here quoted blindly fromTheopompusand that he had no first-hand nowledgeof this process,whichmaynot have evenbeenin usein his day. It is almostcertainthat Strabo never traveledin the part of Asia Minor whereAndeirawaslocated.34On this basisalone,he could not havehad a first-handknowledgeof the process.Moreover,he givesno indicationanywherein his Geographyhat he possessedany understandingofmetallurgy.Hence thispassagedoesnot constituteevidence thatorichalcumwasmadeby the directalloyingofcopperand zinc at the timeof Strabo.

It would seem ratherto indicate that the alloywasmadein this wayat the time of Theopompusor earlier, and that the Greek wordòpEÍxaÀKoslso meantan alloyofcopperandzincat this earlierperiodin spite of the lack of archaeologicalevidence thatbrass wasknownto the Greeks n the fourth enturyb.c. orearlier.

Various Greekwriters, ome earlier and some later thanTheopom-pus, mentionôpeíxotÀKOçs a particularmetal or alloy,usuallyin awaythat indicates that it was one of considerablerarity and value.The earliest suchmention s in the anonymousShieldofHerakles35

almostcertainlycomposed priorto 500b.c., in whichthe poet says,36WQhrcovKvrmïSaçpeixócÂKioaeivou'Hçaíorov kAutòScopa,tte iKvi^iiņaivOrļKev.Sohespoke,andplacedabout hislegshisgreavesofshiningoreichalkos,heglorious giftof Hephaistos.)Somewhatlateris a passagein one of the Homerichymnsto Aphrodite37n which theanonymous poetrelatesthat the Hours attached to the ears of thegoddessan ornament of precious goldand orichalcum. The text3834Leaf,W.f trabo ntheTroadCambridge,923), p.xxviii-xxxviii.35Usuallyncluded neditions ftheworks fHesiod.38 . 121-122.37VI,v. 8,9.38AccordingoAllen, . W.,Halliday,W.R.,andSikes,. E., TheHomericHymnsOxford,936), . 73.



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20 Orichalcum and Related AncientAlloysreads npart KaAfļvpv/cjeirjv,v8èTprļToīaiAoßoiaivvôen'öpeix^ÄKOvXpuaoióte ti^êvtoç. Plato in his Crítias probablywritten nearthe middle of the fourth century, refers to the metal in severalpassages39n his descriptionof the mythicalisland of Atlantis. Indescribing he walls aroundthecapitalhesays tou 8' êvTÒçonrrrépcpTTEpiETTļKov,òv 8èTcpi aŪTTļv TļvKpÓTroÀivpeixá^Kcc aap|JiapvyàçEXovTim/pco8eiç.Theycovered the interiorwall with fusedtin, and

the wall around theacropolisitselfwithoreichalkos,hichhas a fieryresplendence.)As to the temple of Poseidon on the Acropolisherelates that TTccvtciè?Çco0evCpirjXeiyavòvvecoápyúpco,tàtjv ooČCKpCOTTļfcO, TÒ 8èdKpCOTYipiaP^0 CP*à 8' èVTÓÇ,TļV-lèvpO


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Origin of Orichalcum 21morethan a name Kaìtò vuvòvoiJiaLónevovjóvovòte 8è TTÀéovvójjia-toç fļv.But this statement maymeanmerelythat the alloywasnotin use at the particulartime whenPlato wrote,or that it was in usewithout Plato beingawareof it. Possiblyhe was notaware ofit be-cause itwasno longerusedlocally.

The exact nature of the metallurgical processso briefly escribedby Theopompushas been thesubjectof much controversy, nd has

almostinvariablybeen treated as thoughthe account wasoriginalwith Strabo.However,the questionof its true authorshipdoesnotaffect he problemof ts interpretation rom he metallurgicaltand-point.Thisproblemmay convenientlybe discussedby a systematicexamination of themeaningof the words,phrasesand sentencesofthe account. The translationpreviouslygivenwill be usedas a basis,but any additional or alternatemeaningconveyedby the Greektextwillalso be considered.

There is a stone near Andeira whichyieldsiron when burnt/'

The Greek wordÀfOoç,ere translated as stone,had a much broadermeaningthan is indicatedby this usual Englishequivalent,for itincludedany hard substanceof mineral origin. Here the contextclearlyshowsthat some metallic mineral or ore is meant. Andeirawasthe name of a town in northwestern sia Minor,but its exact site isunknown.41Any correlation of its location with known mineral de-positsor ancientminingsites is therefore mpossible.The verbheretranslated as burnt might perhaps be better translated as smeltedsinceit seemsprobablethat the processinvolved thereductionof

somemineralor ore that containediron,althoughthe suggestionhasbeen made that it was a simple roasting processwhichyieldedaproductthat merelyhad thesuperficial ppearanceof ron,42hebasisof this suggestionbeingthat no reducingagent is mentioned.How-ever,the metallurgists f the periodcouldrecognizeronwith certain-ty since this metal wasbeingregularlyproducedon a considerablescale. Hencereductionmusthave been one of thestepsin the process.Very likely the need for mixingthe ore with charcoalin order toobtain iron in a smeltingoperationis not explicitlymentionedbe-

41Leaf,W.,Strabo ntheTroadCambridge,923), p. 284-287.42Helm,O.,VerhandlungenerBerlineresellschaftürAnthropologie,thnolo-gieundUrgeschichte1895),pp.622-623.



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22 Orichalcwm and Related AncientAlloyscause this wassuch a commonpractice.However,it seems almostcertain,from hekind of ore that was apparentlyused,that the firststep in the wholeprocesswas the roastingof the ore, and that noreducing agentwas addedin this step.Theidentityof this ore is notentirely ertain, thoughthe remainderof the account would seem toindicate that it was one that containedzinc aswellas iron.Theonlycommonore that meets this requirements zincblende,impurezinc

sulfide,whichusually contains a considerableproportionof iron.Diergart43was of theopinionthat zinc blende wasunlikelybecause nomention s made of thechoking ulfurdioxidefumes hat wouldhaveresulted fromroastingor smelting t. However,the writer of the ac-count may not have been aware ofthis, or may simplyhave notconsidered t worthmentioning.Aroastingoperationwouldhave beennecessaryas a first tep in order to convert zinc blende to a formsuitable forreduction, .e., to a mixture of iron and zincoxides.If areducing gentwere then addedandthesmeltingdone without pecial

apparatusor precautions, he zinc would havebeen lost andonly ronwouldhave been obtained.In otherwords, f this stone found n thevicinityof Andeira was smelted n theordinarywayonlyironcouldbeobtainedfrom t. But the writer f the account apparentlygoesonto state how a second metal could be obtainedfrom his same orebya specialtreatment.However,an alternate nterpretation s that thestone wasa simpleiron ore and that the second metal was obtainedonlybecausea different re was addedin the secondstep.

Afterbeingtreated n a furnacewitha certain earth t yields drops

of false silver. Theidentity of the earth with which the roasted orewastreated has beenthe subjectof controversy. he Greek wordyfjincludedany kind of friable or soft material that occurredin theground,or any artificialproduct of this sort obtained by treatingmineralsubstancesin various ways.Here it wouldappear to be anatural product. Both Rossignol44nd Diergart45uggestedthat itwas a fluxof some kind. Helm46uggestedthat it was ordinary oal or43Diergart,., Journal ürpraktischehemieCLXXV(1903),PP- 326-334,429-432.44Rossignol, .P., LesmétauxansVantiquitéParis,1863),p. 253.45Diergart,., Journal ür raktischehemieCLXXIV(1902),p. 343.46Helm,O.,VerhandlungenerBerlineresellschaftürAnthropologie,thnolo-gieundUrgeschichte1895),p. 623.



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Origin of Orichalcum 23an earthycoalwhich acted asa reducing agent,and Leaf47 dentifiedit as lignite,but Diergart48 egardedsuch identificationss doubtfulbecause he believedthat anyform f coal would have beendesignatedby its usual genericname.Moreover,no reducingagentforobtainingiron from he ore is mentioned n the first tep of the process,and itseemslikelythat the use ofa reducingagentis alsoimplicithere.Ifthe stone of Andeira wasan ironore,the earth mentionedheremust

have beena zinc ore of somekind. Themost ikelypossibility, ecauseof its commonoccurrencen the generalarea, is calamine. Themainobjectionto its identifications calamineis that this ore usuallyoc-curs n the form f a ratherhardcompactmineralwhich Greekwriterswould calla stonerather than an earth, but perhapsit was calaminethat had beenrefined y roastingto drive out the combinedwater,and then pulverized.Suchpreliminary reatmentwouldhave beenalmostnecessaryfor the successfulsmeltingof this ore. On gram-maticalgrounds,the objectionto the identification f the earth as

calaminein any form s that it is the stone ofAndeira,not the earth,which s said toyieldthe falsesilver,but this statementcouldwellbebased ona lackof understandingof the chemistry f the processbythe ancientmetallurgists r by the writer f the account.Somesigni-ficancemay be attached to the fact that this earth is alluded to insucha vagueway,withouta specificnameand withouta mentionofits source.Possibly,in their desire to preservesecrecy,the metal-lurgists deliberatelywithheldthis information, s well as other es-sentialfacts,from he writer of the account. This sametendencyto

secrecyn regardto what mayhave been thesame mineralsubstanceappearsto occur in at least one later Greek accountin which theauthor fails to identify y eithername orplaceoforigina particularearth used in makinga copperalloywhichmayhave beenbrass.

Whatevermayhave beenthe exact identitiesof the oresand otherrawmaterials usedin the process,and whatevermayhave been thevariousessential but unmentionedworkingdetails,there seems to beno doubt that the false silver producedin the secondstep was moreor less pure zinc. It must have been a white metal that resembled

silver but was not silver,and in all probability t also was not tin or47Leaf,W.,Sir boontheTroadCambridge,923),p. 289.48Diergart,., Journal ür raktischehemieCLXXV(1903),pp.330-331.



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24 Orichalcumand Related Ancient Alloyslead since either wouldhave beengivenits usual name.This leaveszinc as theonlypossibility mongthe metals known n Greektimes.Diergart49was of the opinionthat pure zinc could nothave beenproducedin this processin view of the likelihoodthat the reductionto zinc could not haveoccurred withoutthe simultaneousformationof ron. He concludedthat the productwasan alloyofthe two metalscontaininga fewper cent of iron. However,suchimpurezinc would

have servedalmost as well aspurezinc for lloyingwithcopper n thelast stepofthe process.Thereis alsothe possibilitythat the zinc wasseparatedby distillation.The Greekverb oarooTccilein the text ap-pearsto implythe productionof the zincin drops,or drop by drop,whichat least hints at a distillationprocess.Leaf50nterprets thepassagein this senseby translating s follows: NearAndeirathere sa stonewhich whencalcined becomesiron;and then,whentreated nthe furnace with a certain earth, distills mock silver. Helm51sug-gestedthat the reduction was carriedout in a vesselwith a tight

fitting over, and that the vessel was alsoprovidedwith an outlettube in the bottom nto which the zincvaporpassedand condensed,finally o emergeas dropsof molten metal from he bottom of thiscondensertube.Thoughthis kind of apparatushas beenusedfor theproductionof zinc in modern times, no archaeologicalor literaryevidenceexists for the use ofany suchapparatusin ancient times.However,it mighthave beenpossibleto condensethe zincin dropsonthe wallsand fluesofa furnaceofspecialdesign f a largeexcessofcharcoalwas used for the reduction,though the efficiency f the

operationwouldprobablyhave beenlowbecause ofthe loss ofmuchof the zinc through oxidation.If the metal had been obtainedbydistillation t would,of course,have beenpurer than any metalob-tainedwithoutsuchseparation.

This,addedtocopper,forms he so-calledmixture,which omecalloreichalkos. The metalto whichthe zinc wasaddedmayhave beenbronzerather than copper,for xolKkóhere translatedas copperis ageneric ermthat includedat the time of this accountanymetalthat

49Diergart,., Journal ür raktischehemieCLXXIV(1902),p.339-345-50Leaf,W.,Strabon theTroadCambridge,923),p. 284.51Helm,O.,VerhandlungenerBerlineresellschaftürAnthropologieEthnolo-gieundUrgeschichte1895),p. 623.



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Origin of Orichalcum 25had the generalappearanceof copper.Hence it includedordinarybronzeas well ascopperitself. ndeed, since bronze was more com-monlyused formostpurposes,the wordmore oftendenotes thisalloythan unalloyed copper. Onlywhena modifying djective is used isthereany certainty s to which s meant.Hence thealloyformedbyfusionwith zinc couldhave been either brass or zinc bronze,andconsequentlyoreichalkos ouldmean either one.

ThoughKpajjiameansmixture n general,it usuallymeans mixedwine,and less oftena medicinalmixture. Its use here to denote amixture of metals is quite exceptional,and this appearsto be in-dicated alsobythe useofkoAóiíevovso-called).PerhapsKpSiaas herea technical term that would be better translated as mixed metal. Itstranslation s amalgamby Leaf52 s notsatisfactory ince this term snowgenerally eservedfor n alloythat containsmercury s one of tscomponents.

From thestandpointofthehistory f zincandits alloyswithcopper

thisaccountbyTheopompussimportantnotonlybecause itcontainsthe earliest mention of a processfor the isolationof this metal butbecauseit also containsthe earliestmentionof the manufacture f analloy containingzinc and copper.No other ancient author exceptStrabo,who merely repeats the accountof Theopompus,describesany processthat can beinterpreted s involvingthe direct alloyingofzinc with copperor bronze. This method of makingbrass or zincbronzeapparentlyneverwasused eithercontinuouslyor on a largescale inancient times.Accordingto all the evidence,nonebut the

cementationprocesswas employedwhen orichalcum came to bemanufactured egularly n a largescale inRomanImperialtimes.Certainaccountsin the works of Greekwritersof the Hellenistic

periodhave often been cited as containingallusions to the manu-facture f brass,but unfortunately hese accounts areevenmore am-biguousand sketchythan the one by Theopompus.The earliest ofthese Hellenisticaccountsis containedin the treatise OnStonesbyTheophrastusof Eresoswritten near the end of the fourth enturyb.c.Thisaccountreads as followsì6icot


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26 OrichalcuMand Related Ancient Alloysearth is the one mixedwith copper;for n additionto meltingandmixing, t also had theremarkablepowerof mproving hebeautyofthe color.)53Amongthose whoassume withoutquestionthat this ac-countrefers o the manufacture f brassby the calaminecementationprocessare Rossignol,54Rickard,55nd Forbes.56Thevalidityof thisuncritical conclusionwillnowbe examinedbriefly.

In the first laceit is uncertainthat ordinarycopperis the metal

that was treatedwith the earth. In another section of this sametreatise, whereTheophrastusdescribes thepreparationof verdigrisby the action of sour grape residueson copper,he uses the termXoAkòç pvôpòçred copper)for the metal that was employed,whichclearlyindicates that unalloyed copperis meant. The lackof thisqualifying djectivein the above accountmakesit appearlikelythatthe metal treated with the earth was bronze rather than copper.Inthe secondplacethere s no evidence ofany kind that the earth wascalamine,or anyotherkind of zinc ore.It could have beenanyone of

a number of earthy minerals. Theexistence in ancienttimesof thepracticeof meltingmetals with variousmineralsubstances of thiskind is shownby the many recipesin the LeydenPapyrus X thatdescribe thispracticeexplicitly.57ome of thesesubstances werearse-nic minerals,such as realgar, whichserved to whiten the copperthroughthe formation f a copper-arseniclloy, others were clayeymineralswhich servedto exclude airfrom hesurfaceof the metal onfusionand thus preventoxidation,and still others were bituminousmaterialswhichserved to reduce metal oxides on fusionnd produce

clean metal.There aretwoindicationsthat the unusual earth n thisaccount wasa bitumen of some sort.Oneis the meltingof the earthand the other is the mention by Theophrastusin the very nextsentencefollowing his account of anotherpeculiarearth that wasundoubtedlya natural bituminous substance.58houghit is possible53Text and translationccordingo Caley, . R., and Richards,.F. C.,TheophrastusnStonesColumbus, 956),pp.26,55.54Rossignol, .P.,Les métaux ansVntiquitéParis, 863), . 254 footnote).55Rickard,. A.,Man andMetalsNewYork,1932),p. 157.66Forbes,R.J., Metallurgyn AntiquityLeiden,950),p. 278.57Berthelot, .,

Archéologiet histoire essciences

Paris,1906),pp.268-283,290-291, 96-299.58Caley, . R., and Richards,.F. C., Theophrastusn StonesColumbus,1956),p.167-169.



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Origin of Orichalcum 27that Theophrastusin this accountis alludingto the manufactureofbrass or zincbronze, t seemsmuch moreprobablethat he is alludingto a mererefining rocess in whichbronze,in the formof crude orscrapmetal,was melted witha naturalbituminous materialin orderto obtain cleanmetal of improvedappearance.

Alsofrequently ited as evidence for the manufactureof brass inGreek timesare two accountsin the pseudo-AristotelianworkOn

MarvelousThingsHeard a compilationusuallyattributed o studentsor successors ofAristotle, nd believed tohave beenwrittenfor themostpart in the third enturyb.c.,though omepassagesof this workare evidentlybased on earlier sources. Thefollowingccount,whichcomprisesll of sec.49,is apparentlybased,at least in part, onsuchsources: Oaai5èKaiev 'IvSoïçtòv 'c('kòv oütcoseivaiAaixrrpovaiKa0apòvKaiccvícotov,berre riSiayivcboxeaOait¡ póa Trpòsòvxpv-CTÓv,cAV v oïçAapefourorripíoiçaTiaKcxsivaiTivaçKaittàeíouç,çeinr| TT) ècnarj,ÀÀcoçúk fļvSiayvcovai TTÓTepóvïcri aÀKaïfļxpv/caT.(Theyalsosay that amongthe Indians the bronze is sobright, leanand freefrom orrosion hat t is indistinguishablen appearancefromgold,but that amongthecupsofDarius there sa considerablenumberwhich ouldnotbedistinguisheds bronzeorgold except bytheodor.)

On the basisof this accountPartington59emarks hat, Brass wasprobablymade in Persiain the AchaemenianPeriod,since Dariusissaid to have had abowllikegoldin appearancebut distinguishableby its unpleasantsmell. Forbes60ppears to followPartington inpart when he asserts that, In Iran brass came into use in the

Achaemenian Period. Dariusis said to havepossessedan 'Indian' cupwhich ookedlikegoldbut had a disagreeablesmell,whichpointstobrass. Certain naccuraciesareapparent n thesepartial paraphrases,but the main pointis that neither he tentative remark ofPartingtonnor the positiveassertionof Forbescan be justifiedon the basis ofthis account. Thereis eventhe possibilitythat this account may bean exaggeratedorfanciful raveler'stale,but even when takenliteral-ly it providesno real evidence for the use of brass in either ndia orPersia at the time of Darius.

69Partington, . R.,OriginsndDevelopmentfAppliedChemistryLondon,1935)» -410-60Forbes,R.J., MetallurgynAntiquityLeiden, 950),p. 279.3



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28 Orichalcumand Related Ancient AlloysIn the text the wordxoAkóçs usedto denote the metal that is like

goldin appearance. Usuallythis has been translatedas copper,but,since it is obviouslyyellowin color,bronze is a much better trans-lation. There is nojustification ortranslating s brassmerelyon thebasis ofcolorsincepolishedbronzeof proper tin content may alsoresemblegoldor certaingoldalloysrather closelyn color.Moreover,in anotherpart of this samework(sec.58)a distinction s madebythe use ofdifferent ords between the metal of a certainbronze statueand the metal of others made of oreichalkos.After ome remarks onthe copperdepositsof the island ofDemonesus,the writer goeson tosay:žcrri è aCrróôicìKkòKoXv/|ißr|TfisvSuoivòpyuialçTfjç oàckjot1s#õôevó êvZiKucovi oTivávBpiccçv tcoápxaícoveco ou'AttóààcovosKaiêvQevecpí òpeíxaÀKoikoàoúhevoi.Thereis alsocopperto be divedfor n two fathomsof sea. Fromthis is made the statue in Sicyoninthe ancienttempleofApollo,and thosein Pheneuscalledoreichalkosstatues.) From the wordingit might seem that these statues were

composedof the copperitself, but in view of the fact that Greekstatues generallywere made ofalloyed copper,the correctmeaningmust be that the copperwas usedin makingthe alloysfor thesestatues. It mayalso be notedthat noarchaeologicalevidence exists forthe use of brass or zinc bronzen India or Persiaat the time of Darius.

Thesecond accountin the work On MarvelousThingsHeard whichmeritsmore serious and extensiveconsideration,omprises ll of sec.62,and reads as follows: DotalòvMoœovvoikovoAkòvÀaiiirpÓTaTovKai ÀeuKÓTaTovivai, où irapaniyvunévouŮTCpKaaxjrrépou,cÀÀà

yfjç tivòç aCrrouyivoiiévrjsai ovvevyo|iévr|çCrrcp.Àéyouai8è tòveůpóvTaTTļvpScTivirjôéva i8ccÇariòTa -rrpoyeyovÓTavToIçóttoisXaÀKconaTa iá


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Origin of Orichalcum 29could not have been copperitself,but must have been an alloyofcopper.The wordx°^kòç maymean eithercopperor bronze,andbronzeseems the bettertranslation.However,from he standpointofgrammar hereflexive ronounat the end of the phrasethen appearsto refer ack to bronze,and thisposesa difficulty rom hestandpointofmetallurgy, orobviouslytin would notbe added to bronze but tocopper.Asindicatedby the translation hisdifficultymayberesolved

by assumingthat the reflexivepronounrefersback to x°^kòsin itsalternatemeaningof copper.The wordÀevKÒTorovsed indescribing heappearanceof the alloy

maybe translated as verywhite nsteadofvery pale or very ight ncolor. f thisword s sounderstood, hen the alloycould nothavebeenordinarybronze or brass.Tin bronzescontainingmore than 25 percent of tin are white and so arebrassescontainingmore than 75percent ofzinc,thoughsuchalloysare too brittle formostpracticaluses.But there s anotherpossibility. t could have beena copper-arsenic

alloy, for such an alloy, even when it contains a relativelysmallproportionof arsenic,is also white.Alloysof copperwith arsenic,whichmaybe calledarsenicbronzes,wereknown n the Aegean regionfromvery early times, as has been shownby chemicalanalysesofcertainprehistoricmetalobjects.61Moreover,he existencein ancienttimes of the practiceof whitening opper by treating t with arsenicminerals,or with productsderivedfrom uchminerals, s shownbytworecipes n the LeydenPapyrusX. One of these(No.23)readsasfollows

XaÀKOÛeÚKoaiçXaÀKÒvÀ6UKÒVroifļcrat,ootspeiyéaôai ccoT)|Jcp,aovïaco,Kaiccvév-KÀT1TOVivar AaßcovyaíhKÒvúnpiov,yevvevcjov,aAcbvlçTtļv ivãv


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30 Orichalcum and Related Ancient Alloyshavingadded for achmina2 drachmasofdecomposedironyrealgarand 5 drachmasof amellosealum,and cast it. For the secondfusion4 drachmas of Pontic waxare added; if not, it is burnt by the fireand breaks.)

Probably the decomposedrealgar mentionedin this recipe wasobtainedby roastingthe natural mineral,possiblyunder reducingconditions whichwouldproducea mixture of arseniousoxide and

arsenichavinga greycolor.The alumperhapsserved as a flux. Boththe roastedarsenic mineraland the alum wouldhaveancientlybeenclassified as earths. The waxprobablypreventedoxidationof thecopper-arseniclloy. Oneobjectionto this recipeas a parallelto theaccountin the workOn MarvelousThingsHeard is thediscrepancyntime. The Leyden PapyrusX wasprobablycompiledin the thirdcenturyA.D.,whereas the accountwasprobablywritten n the thirdcenturyb.c.,and thewordingwouldappearto indicate that the proc-ess itself was evenearlier.However,many of the recipesin the pa-

pyrusundoubtedlyrepresent echnicalprocessesthat had been in usefor a very long period.Whetherany credencecan be placedin thestatement n the second sentenceof the accountas to the lossof theknowledgeofthe processsperhapsdoubtful ince the mentionof ostarts is a favoritedevice for ddinginterest ostories.

In view ofthe possibilitythat the bronze of the Mossynoeci mayhave beena copper-arsenicalloy, it cannot be unquestionablyas-sumed,as somanyhave done,that the earth mentioned n this ac-count is calamine andthat the alloy producedwithouttin is brass.

Nevertheless,there is a considerableprobabilitythat the accountdoesalludeto the manufactureof brassby the cementationprocess,and that it is the earliest knownallusion tothis process.What seemsto supportthis view is that the onlyknownGreekobjects composedof brass or zinc bronze(TableIII) have beenfoundat or near thesites of coloniesor settlementson the BlackSea,near the shore ofwhich, n Pontus,dweltthe peopleknownas theMossynoeci.Evenifthis accountin the work On MarvelousThingsHearddoes notalludeto a processfor makingbrass,it is still important, s is likewisethe

onein the treatise On Stones of

Theophrastus,for

explaininghow the

manufactureof brass by the cementationprocesscame to be dis-covered.Oncethe practiceofheatingvariousmineral ubstanceswith



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Origin ofOrichalcum 31coppercame intouse,it was inevitablethat sooneror later zincoreswouldbe heatedwith the metal in the presenceof a reducing agentand brasswouldbe produced.What remainsunknown, nd probablyalwayswill remainunknown, s exactly where and whenthis dis-coverytookplace.Largelyon the basisof the accountjust discussed,Forbes63believes that the discoverytook placein Pontus, but theevidence seems tooincompleteoestablish this withcertainty.Forbes

is also of theopinionthat the discoverytookplacein the first alf ofthe first milleniumb.c.,but real evidence for suchan earlydate ap-pearsto be lacking.The availableliterary videncedoes not indicatea dateanyearlierthan the fourth enturyb.c.,and thearchaeologicalevidence does not indicatea date any earlier than the secondcenturyb.c. at the earliest. It was not until after the middle of the firstcenturyb.c. that the intentionalmanufacture f brassby the cemen-tation process beganon any considerablescale,and its manufactureby this processon a continuousand large scaledid not beginuntil

after the foundation of the RomanEmpire.The essential differencen compositionbetweenthealloys producedbefore the middle of the first entury b.c. and thoseproducedlaterhas alreadybeenpointedout. Another distinct difference s in theiruse. The earlieralloys were never used for coinage,whereastheorichalcumofthe Romans was usedchiefly or oinage,and indeedatthe beginning nd for a considerable timeafterwards his appearstohave been itsonlyuse.Ourknowledgeof the compositionoforichal-cummust therefore e derived chiefly rom nalysesof Roman Im-

perialcoinscomposedof this alloy.63Forbes,R. J., MetallurgynAntiquityLeiden,950),pp. 279-280.



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IV. PREVIOUSANALYSESOF ORICHALCUM COINSOFTHE ROMANEMPIRE

Thefirst nalysesoforichalcumcoins,which, ndeed,were the first

quantitativeanalysesof brass objectsofany kind,were madeby thecelebratedpioneer analytical chemist Martin Heinrich Klaproth.Thoughhe announced the resultsof his investigationn a paperen-titled Mémoire denumismatiquedocimastique read beforetheRoyalAcademyof Sciencesand Belles-Lettresof Berlin on July 9,1795,the first publication64f these results was delayeduntil 1798.Theresultsofhisanalysesas hereported hemare shown n Table VI.These same resultscalculated ona percentagebasis are showninTable VII.Asmightbeexpectedfrom he state of numismaticknowl-

edgeinhisday,hisdescriptionsf the coins he analyzedareimperfect,though they are adequatefor pproximate dentifications indicatedin Table VI. His method ofanalysis,which he had to devise for thepurpose,was inadequateby present standards and could notyield

TABLEVIANALYSESF SESTERTIINDDUPONDIIY KLAPROTH

Coin Copper Zinc Tin Lead Iron TotalNo. Grains Grains Grains Grains Grains Grains

1 119 31- - -

1502 187 46 - - - 2333 296 84 - - - 3804 293 59 3 4 1 3605 326 53 3 - - 3826 294 60 11 - - 365

64Klaproth,M.H.,Mémoires eVcadémieoyalees sciencest belles-lettresBerlinClasse dephilosophiexpérimentale1798), pp.97-113.A Germanversion fthis amepaperwas aterpublishednSammlungerdeutschenbhandlungenwelchender öniglichenkademieerWissenschaftenu Berlin or-

gelesenurdenn den

Jahren 792-1797, xperimental-hilosophie1799),p.3-14,under hetitle Beitragurnumismatischenocimasie,ndstill aterunder he ame itle hereppeared modifiederman ersionnAllgemeinesJournal erChemieVI (1801),pp.227-244.

32



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Previous Analyses of Orichalcum Coins 33accurate results.However,t seemslikelyfrom ater analysesofsimi-lar coins that the percentagefigures or he maincomponents, opperandzinc,shownn TableVII, are not in error y any more than aboutone per cent. Alreadyapparent from this first eries of results arechronologicaldifferencesn the compositionoforichalcum.

Descriptionss Given y Klaproth

l.Obv.: Castorand Polluxas two horsemen,with the inscriptionCAESAR AUGUSTUSGERMANCUS.Rev. SC in centerwith llegible nscription.Wt. = 150grains 9.7grams].

2. Coin of NeroandDrusus,ons ofGermanicus.Obv. Quadriga.Rev. An ndistinct igure hich riginallyepresentedither nuprightsoldieror a trophy.Wt. = 233grains 15.1grams].

3.Obv. Head of TiberiusClaudius.Oblongcounterstampehindhead.

Rev. Civic crownwith nscriptionEX S C OB CIVESSERVATOS.Wt. = 380grains 24.6grams].

4.Obv. Head ofVespasian.Rev. Soldier eated.Wt. = 360grains 23.3grams].

5. Obv. Head ofTrajan.Rev. Seatedfigure, ossiblyVesta.Wt. = 382grains 24.8grams].

6. Obv. Head ofTrajan.Rev.: SameasNo. 5.Wt. = 365grains 23.7grams].

Identifications1.DupondiusofCaligula,A.D.37- 412. DupondiusofCaligula,A.D.37- 413. Sestertius fClaudius,A.D.41- 434. SestertiusfVespasian,A.D. 71- 735. Sestertius fTrajan, a.D. 98-1176. Sestertiusf Trajan, a.D.98-117

After he publicationofthe analysesofKlaproth,no results of anyinvestigationof the compositionof orichalcumcoinswerepublished



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34 Orichalcum and Related AncientAlloysforhalf a century xcept the results of an analysisofa singlecoinbyGöbel.65He describedthis coin asfollows:

Obv Tiberius ClaudiusCaesar.Rev. Bust of AntoniaAugusta.

TABLEVIIANALYSESF KLAPROTHALCULATEDS PERCENTAGES

Coin Copper Zinc Tin Lead Iron TotalNo. % % % % % %1 79.3 20.7 - - - 100.02 80.3 19.7 - - - 100.03 77.9 22.1 _ - - 100.04 81.4 16.4 0.8 1.1 0.3 100.05 85.3 13.9 0.8 - - 100.06 80.6 16.4 3.0 - - 100.0

This wasevidentlya dupondiusof Claudius struckn A.D.41. Göbel

reportedthat the metal of this coin was composedof 72.20% copperand 27.7%zinc. These resultsmustberegardedas only approximate,forhe found no othermetals and his method ofanalysiswas notverygood.Anothercoin,which Göbelevidentlytook to be Roman,wasalso analyzedand found to contain 10.5%zinc. However,his de-scription ndicates that this coin was a modernforgery.Göbel alsoanalyzeda numberof brass antiquitiesfoundin the Russian Balticprovinces, fewof whichwereprobablyof Romanorigin.Thecompo-sition of these is discussed later.

A smallseries of orichalcumcoins wasanalyzed byPhillips.66Hisresults,recalculated onthe basis ofpresentatomicweightsfromhisanalyticaldata, are shownin Table VIII.Thoughthese resultsareprobablymore accurate than those obtainedby Klaprothor Göbel,they are by no meansfree from rror s is indicatedby the unsatis-factory ummationsoftwo ofthe analyses.Hisimperfect escriptionsand the correspondingdentifications re also shownn the table. Inaddition tothese four oins,Phillips analyzeda sestertius f Faustina

65Göbel,., ÜberdenEinfluß

er Chemieuf dieErmittelunger Völker erVorzeit derResultate er chemischenntersuchungetallischerlterthümer(Erlangen, 842),p. 29.66Phillips, .A.,Journal f he hemicalociety,V (1852),p.252-300.



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Previous Analyses of Orichalcum Coins 35Junior, which he found to containa higher proportionof lead thanzinc and almostas much tin as zinc.The metal ofthis coin shouldproperlybe classedas a zinc bronze.

TABLE VIIIANALYSESF SESTERTIINDA DUPONDIUSY PHILLIPS

Coin Copper Zinc Tin Lead Iron TotalNo.

% % %% % %

1 82.38 17.36 - - 0.36 100.102 81.07 17.82 1.05 - - 99.943 83.13 15.90 - - 0.51 99.544 85.77 10.89 1.15 1.74 0.75 100.30

Descriptionss GivenbyPhillips1.LargeBrass ofthe CassiaFamily.About 20 B.c.

Wt. = 365grains 23.7grams].2.LargeBrass of Nero. A.D. 60. Rev.:Rome seated.

Wt. = 435grains 28.2grams].3. Titus.A.D.79.Wt. = 178grains 11.5grams].4. Hadrian.A.D. 120.Fortunae educi

Wt. = 365grains 23.7grams].

Identifications1.Sestertiusf Augustustruck nder C.CassiusCeller smoneyer.2. Sestertiusf Neroprobablytruck n theperiodA.D. 64-66.3.Dupondiusof Titus. Thestateddateisprobablyorrect.4. Sestertiusf Hadrian which ouldhave beenstruck t various imesn

the periodA.D.117-138.

Amonga considerable number of ancientobjectsand materialsanalyzed byGiradin67was asingleRoman orichalcum coinwhichhedescribedashavingon one sidea bust of AntoniaAugustaand ontheotherthe inscriptionTitus Claudius CaesarAugustus Imperator.Theimprobablereading Titus was apparentlybased onthe first woletters which in all probabilityshould beinterpreted s Tiberius .Onthe basis of this nterpretation he coin wasprobablya dupondiusof Claudius struckn A.D.41. Giradin foundthat the coin contained

81.4% copperand 18.6%zinc. No other metals werereported nd nogreat accuracycan beascribedto his results.67Giradin, .,Journal ür raktischehemieLX(1853),p. 92.



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36 Orichalcum and Related AncientAlloysGenth68nalyzeda coin ofTrajan and one of Hadrian. Sincehe

gaveneitherweightsnor descriptions, he denominationsand exactdates ofthesecoinsare unknown. His results are shownn Table IX.No.i was the coinofTrajan and No.2 the coin of Hadrian.Thoughhis analysesare morecompletethan those of his predecessors,heiraccuracyis not highas isshownby the highsummations.

TABLEIXANALYSESFCOINS FTRAJANNDHADRIAN YGENTH

Coin Copper Zinc Tin Lead Iron Silver TotalNo. % % % % % % %1 88.58 7.56 1.80 2.28 0.29 0.21 100.722 86.92 10.97 0.72 1.10 0.18 0.30 100.19

Theresultsobtainedby Genthhavehada curioushistory f carelesscitationbylaterwriters. ibra69 noneplacewrongly scribed the firstset of results to Phillips,and in anotherplacehe ascribed bothsetsto

himself.Moreover,Bibra interchangedthe names of the emperors.Stohman and Kerl70 scribed both sets of results toPöpplein. Ap-parentlythese writersdid not consult the original publication.

The most extensiveearlyseries of chemicalanalysesof orichalcumcoins was carried outby Bibra.71His results are listed in Table X.Unfortunately, he coins heanalyzedcannot becloselydated since hegaveonly the names of the emperorsand the weightsof the coins.The denominations f the coins shownn the table have been decidedfrom heseweights.Theperfect ummationsof his analysesarise from

the fact that he determined opperby difference,.e., he subtractedthe percentagesofall the othercomponentsfrom 00.00%in ordertoobtain the percentageof copper.This means that the accumulatederrors f allthe other determinations ellonthe copperwhichresultedin a correspondingrror n the determinationof this element.Hisdeterminations f some of the other elements may also besomewhatin error. For example,it is certain from his method of analysisand68Genth, . A.,Journal f he ranklinnstitute, XXVI(1858),p. 266.69Bibra, .von, ie Bronzen ndKupferlegierungener lten nd ltesten ölker

(Erlangen,869),pp.60-61,

64-65.70Stohman,. andKerl,K.,EncyklopädischesandbucherTechnischenhe-mie Braunschweig,888-1905),V, pp.2013-2014.71Op.cit.,p.52 55.



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Previous Analyses of Orichalcum Coins 37from he resultsof ater analysesthat his stated percentagesof nickelare generally oohigh.In spiteof theseuncertainties, heanalysesofBibraprovidemuchvaluable information.

TABLE XANALYSES FORICHALCUMESTERTII NDDUPONDII Y BIBRA

Coin Copper Zinc Tin Lead Iron Nickel Anti- TotalNo.

mony0/ 0/ 0/ 0/ 0/ 0/ 0/ 0//0 /0 /0 /0 /0 /0 /0 /01 92.57 5.15 1.05 trace 1.03 0.20 trace 100.002 87.05 11.80 0.72 trace 0.43 trace trace 100.003 77.44 21.50 0.30 trace 0.32 0.24 0.20 100.004 88.19 10.23 0.51 0.30 0.55 0.22 none 100.005 86.30 12.94 0.52 trace 0.14 0.10 none 100.006 82.13 15.35 1.12 trace 1.00 0.40 trace 100.007 83.95 12.42 2.22 0.30 0.39 0.50 0.22 100.008 78.24 20.23 0.70 0.13 0.40 0.30 none 100.009 90.76 5.12 3.22 0.70 0.13 trace 0.27 100.00

10 91.24 7.14 0.32 0.44 0.52 0.34 none 100.0011 88.50 9.05 1.27 0.30 0.35 0.43 0.10 100.0012 82.91 15.57 0.60 0.06 0.70 0.08 0.08 100.0013 82.35 16.84 0.43 trace 0.38 trace trace 100.0014 89.92 6.74 1.52 0.37 1.15 0.30 none 100.0015 90.49 7.04 1.10 0.20 1.07 0.10 trace 100.0016 91.72 5.33 1.55 trace 1.30 trace trace 100.0017 87.88 11.28 none 0.09 0.37 0.38 none 100.0018 87.86 8.14 3.86 trace 0.12 trace trace 100.0019 81.47 10.30 6.62 0.02 0.01 0.28 1.30 100.0020 85.63 6.07 4.62 2.00 1.07 0.40 trace 100.0021 90.28 5.90 2.00 0.41 0.91 0.28 0.22 100.0022 87.70 7.92 2.90 0.42 0.73 0.31 0.02 100.0023 85.60 5.77 4.02 4.17 0.13 0.21 trace 100.00

Identificationsnd Notes1. Ses

orichalcum and related ancient alloys : origin, composition and manufacture : with special reference...

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