Chapter 9Chapter 9MineralsMinerals

Section 1Section 1

What is a Mineral?What is a Mineral?

Notes 9-1Notes 9-1

What is a Mineral?What is a Mineral?MineralMineral: a natural, inorganic, crystalline : a natural, inorganic, crystalline solidsolid InorganicInorganic: not made of a living thing or the : not made of a living thing or the

remains of a living thingremains of a living thing CrystallineCrystalline (crystal): natural solid with a (crystal): natural solid with a

definite internal structuredefinite internal structure Every mineral has a specific chemical make Every mineral has a specific chemical make

up; can be a element or compoundup; can be a element or compound Rocks are not minerals; minerals are not Rocks are not minerals; minerals are not

rocksrocksRocks are made up of various minerals and Rocks are made up of various minerals and organic matterorganic matter

What makes a mineral, a mineral?What makes a mineral, a mineral?

Must answer yes to four important Must answer yes to four important questionsquestions

1.1. Is this substance made of inorganic Is this substance made of inorganic material?material?

2.2. Does this substance occur naturally?Does this substance occur naturally?

3.3. Is this substance a solid in crystalline form?Is this substance a solid in crystalline form?

4.4. Does this substance have definite chemical Does this substance have definite chemical composition?composition?

Kinds of MineralsKinds of MineralsRock-forming mineralsRock-forming minerals Form the rocks of the earth’s crustForm the rocks of the earth’s crust 20 out of 3,000 different minerals are common20 out of 3,000 different minerals are common

These 20 make up the rock forming mineralsThese 20 make up the rock forming minerals

10 of these are so common, they make up 90% of 10 of these are so common, they make up 90% of the earth’s crustthe earth’s crust

Quartz, orthoclase, plagioclase, muscovite, Quartz, orthoclase, plagioclase, muscovite, biotite, calcite, dolomite, halite, gypsum, and biotite, calcite, dolomite, halite, gypsum, and ferromagnesian minerals (olivine, pyroxene and ferromagnesian minerals (olivine, pyroxene and amphibole)amphibole)

Minerals can be classified into two major Minerals can be classified into two major groupsgroups

QuartzQuartzOrthoclase feldspar Orthoclase feldspar

(K-spar)(K-spar)

Plagioclase Plagioclase feldsparfeldspar

Muscovite micaMuscovite mica

Biotite micaBiotite mica CalciteCalcite

DolomiteDolomite HaliteHalite

GypsumGypsum OlivineOlivine

Pyroxene - AugitePyroxene - Augite Amphibole - HornblendeAmphibole - Hornblende

Silicate MineralsSilicate Minerals

All silicates contain silicon and oxygenAll silicates contain silicon and oxygen Quartz is purely silicon and oxygenQuartz is purely silicon and oxygen

Other minerals have one or more different Other minerals have one or more different elements attached to the silicon and oxygenelements attached to the silicon and oxygen

Feldspars are the most common silicate Feldspars are the most common silicate mineralsminerals

Orthoclase feldspar has potassium (K) attached to Orthoclase feldspar has potassium (K) attached to Si and OSi and O

Plagioclase feldspar has sodium (Na) or calcium Plagioclase feldspar has sodium (Na) or calcium (Ca)(Ca)

Silicate MineralsSilicate Minerals

Ferromagnesian mineralsFerromagnesian minerals Rich in magnesium (Mg) and iron (Fe)Rich in magnesium (Mg) and iron (Fe) Include olivine, pyroxene, amphibole and Include olivine, pyroxene, amphibole and

biotitebiotite

Silicate minerals make up 96% of earth’s Silicate minerals make up 96% of earth’s crustcrust

Feldspar and quartz make up 50% of the Feldspar and quartz make up 50% of the crustcrust

Nonsilicate MineralsNonsilicate Minerals

4% of the earth’s crust 4% of the earth’s crust Minerals that do not contain silicon (Si)Minerals that do not contain silicon (Si)

Six major groups of nonsilicates Six major groups of nonsilicates (p. 158-159)(p. 158-159)

Carbonates Carbonates (CO(CO33))

Halides Halides (Cl or Fl combined with Na, K or Ca)(Cl or Fl combined with Na, K or Ca) Native Elements Native Elements (uncombined)(uncombined) Oxides Oxides (O and some other element besides Si)(O and some other element besides Si) Sulfates Sulfates (SO(SO44))

Sulfides Sulfides (one or more elements with S)(one or more elements with S)

Crystalline StructureCrystalline Structure

Crystal: natural solid with a definite Crystal: natural solid with a definite internal patterninternal pattern If unrestricted, a mineral will naturally form If unrestricted, a mineral will naturally form

into a single, large crystalinto a single, large crystal However, most often in natural crystal are not However, most often in natural crystal are not

unrestrictedunrestrictedMost form in tiny crystal shapes that must be seen Most form in tiny crystal shapes that must be seen with a microscopewith a microscope

Shapes can be helpful in the identification of a Shapes can be helpful in the identification of a mineralmineral

Crystalline StructureCrystalline Structure

Structure of silicate Structure of silicate minerals always minerals always begins with the begins with the silicon-oxygen silicon-oxygen tetrahedrontetrahedronOne Si to Four OOne Si to Four OCombined in many Combined in many different ways to different ways to produce different produce different mineralsminerals

Crystalline StructureCrystalline Structure

Some to rememberSome to remember Mica: Mica:

forms in sheetsforms in sheets Quartz: Quartz:

framework silicateframework silicate Feldspar: Feldspar:

framework silicateframework silicate

HomeworkHomework

Key TermsKey Terms

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Sticky Note ReadingSticky Note Reading

Ch. 9Ch. 9