Classification of MineralsClassification of Minerals

Native ElementsNative Elements – minerals naturally composed of only one element (e.g., diamond, sulfur, gold)

Sulfides and SulfatesSulfides and Sulfates – minerals containing SO4-2 or S-2 anions

(e.g., galena, pyrite, gypsum)

OxidesOxides – minerals containing O-2 anions (e.g., hematite, magnetite, rutile)

SilicatesSilicates – huge family of minerals which all contain some variant of SiO2 (e.g., quartz, garnets, micas, feldspars, clay minerals).

CarbonatesCarbonates – minerals containing the CO3 anion (e.g., calcite, barite)

OthersOthers – including salts (fluorite, halite), and a several other groups.

Dana Classification System, the complete list of known minerals has 78 categories

Most Common Elements in Earth’s Crust

OAl SiNa Mg

K Ca Fe

OxygenOxygen

SodiumSodium

MagnesiumMagnesium

AluminumAluminum

SiliconSiliconPotassiumPotassium

CalciumCalcium

IronIron

1.8

1.8

1.9

1.9

1.9

1.9

2.5

2.5

3.3

3.3

K

K

K6.

26.

2

20.5

20.5

60.5

60.5

Common Rock Forming MineralsCommon Rock Forming Minerals

QuartzQuartz

Plagioclase feldsparPlagioclase feldspar

Potassium feldsparPotassium feldspar

Pyroxene GroupPyroxene Group

Amphibole GroupAmphibole Group

MuscoviteMuscovite

BiotiteBiotite

These minerals make up more than 90% of the Earth’s crust. These minerals make up more than 90% of the Earth’s crust. AllAll are silicates are silicates

Si O

Percent of atoms in Earth’s crustPercent of atoms in Earth’s crust

O

OO

O

O

O

O

Si

SiSi

Si

Si

Si

Si

Al

AlAl

Al

Al

Fe

Fe

Fe

Fe

Ca

Ca

Na

Na

Na

K Mg

Mg

Mg

Mg

CaSiO2

AlSi3O8

Al2Si2O8

SiO3

Si8O22

AlSi3O10(OH)2

AlSi3O10(OH)2

Other Important Rock Forming MineralsOther Important Rock Forming Minerals

Calcite - major component of limestone and seashells, “3” on Mohs Hardness Scale

Dolomite - major component of limestone

http://www.nrcan.gc.ca/gsc/calgary/geoscape/topics/resources_e.html

Other Important Rock Forming MineralsOther Important Rock Forming Minerals

GypsumGypsum – very common evaporite in arid environments, used for plaster and drywall, “2” on Mohs Hardness Scale

HaliteHalite – common evaporite in arid environments, dietary staple

Clay mineralsClay minerals – basis of most soils

http://news.mpr.org/features/200208/21_losurem_ethanol/

http://militaryspecialtiesinc.com/

http://www.unicef.org/programme/nutrition/focus/micronut/iodine.htm

http://www.rootsweb.com/

Other Important Rock Forming MineralsOther Important Rock Forming MineralsHematiteHematite – major ore mineral of iron

MagnetiteMagnetite – major ore mineral of iron

GalenaGalena – major ore mineral of lead

SphaleriteSphalerite – major ore mineral of zinc

http://mine-engineer.com/mining/

Other Important Rock Forming MineralsOther Important Rock Forming Minerals

OlivineOlivine – useful for interpreting igneous rock formation

Garnet groupGarnet group – useful for interpreting metamorphic rock formation

http://www.whigham.org/Hawaii/ http://www.dsuper.net/~marcouet/my1.htm

http://www1.iwvisp.com/

Evaporite minerals with collector

Minerals form wherever and whenever the molecular building blocks are present and local conditions allow those building blocks to bond.

Local conditions can change dramatically in all of Earth’s mineral-forming environments (both on the Earth’s surface and within the Earth), making for interesting mineral associations.

The rock types (igneous, sedimentary, metamorphic) are defined by the conditions under which they formed.