2.1.3 Classification of minerals
http://www.indiana.edu/~geol105/images/gaia_chapter_5/
crust_composition.jpg
http://www.wou.edu/las/physci/ch462/element%20abundance.gif
Mineral classifications
ƒ
11 groups of classification based on anion –
anionic group
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
Native elements
Sulphide & sulphosalt
Oxides
Halides
Carbonates
Nitrate
Borate
Sulphates & chromates
Phospates
Tungstate & Molybdates
Silicates
Native elements
ƒ ~ 20 elements are found in the native state
ƒ Metals – Semimetals – Nonmetals
– Metals Î gold (Au), silver (Ag), copper (Cu), iron
(Fe), platinum (Pt)
– Semimetals Î arsenic (As), bismuth (Bi)
– Nonmetals Î sulfur (S), diamond (C), graphite (C)
http://www.pegmatite.ru/My_Collection/exchange/sl212.jpg
gold
iron
http://z.about.com/d/geology/1/0/Z/Q/1/stategold.jpg
copper
http://upload.wikimedia.org/wikipedia/commons/d/d7/Native_Copper_(mineral).jpg
silver
http://www.museum-mineral.com/specimens/det1_74.jpg
arsenic
graphite
http://www.choudhery.com/graphite/graphite.jpg
http://www.minerslunchbox.com/images/ml2621.jpg
diamond
sulphur
http://www.kristalle.com/minerals/s_5041.jpg
http://keetsa.com/blog/wp-content/uploads/2008/05/rough_diamonds_picture.jpg
Sulfides & sulfosalt
ƒ Sulfides form majority of ore minerals
ƒ General formula X (S-n), where X = metal
– Galena (PbS)
– Sphalerite (ZnS)
– Pyrite (FeS2)
– Pyrrhotite (Fe(1-x)S)
– Chalcopyrite (CuFeS2)
– Cinnabar (HgS)
– Realgar (AsS)
– Stibnite (Sb2S3)
– Arsenopyrite (FeAsS)
http://www.crystalradio.net/minerals/pyrite.jpg
http://fireflyforest.net/images/firefly/2006/April/galena.jpg
sphalerite
http://cmsc.minotstateu.edu/Labs/web%20minerals/Chalcopyrite.jpg
http://www.gc.maricopa.edu/earthsci/imagearchive/sphalerite755.jpg
stibnite
http://www.palagems.com/Images/mineral_news/stibnite.jpg
cinnabar
http://www.mii.org/Minerals/Minpics1/Cinnabar.jpg
stibnite
http://www.uni-heidelberg.de/institute/fak12/ugc/antimon/Stibnite.jpg
arsenic-orpiment-realgar
http://media-2.web.britannica.com/eb-media/61/13361-004-7F27B853.jpg
Oxides
ƒ Relatively hard, dense & refractory
ƒ Anion = O2- and OH–
–
–
–
–
–
–
–
–
Cassiterite (SnO2)
Pyrolusite (MnO2)
Psilomelane (BaMn9O16(OH)4)
Chromite (FeCr2O4)
Ilmenite (FeTiO3)
Magnetite (Fe3O4)
Hematite (Fe2O3)
Limonite (FeO(OH))
Corundum (Al2O3)
cassiterite
http://geology.com/minerals/photos/cassiterite-stream-tin-601.jpg
http://www.thunderhealing.org/rock/cassiterite.jpg
psilomelane
pyrolusite
http://z.about.com/d/geology/1/0/s/C/1/psilomelane500.jpg
http://upload.wikimedia.org/wikipedia/commons/thumb/0/01/Pyrolusite_dendritic_on_felsite.jpg/350px-Pyrolusite_dendritic_on_felsite.jpg
hematite
magnetite
http://www.melworks.com.au/catalog/images/bhemv42212.jpg
http://www.mchenry.edu/depts/EAS/courses/eas170/Minerals/images/Magnetite.jpg
hematite
http://upload.wikimedia.org/wikipedia/commons/a/ae/Hematite.jpg
banded chromite
http://www.earth.ox.ac.uk/~oesis/field/medium/chromite1.jpg
http://upload.wikimedia.org/wikipedia/common
s/9/9a/Several_corundum_crystals.jpg10
http://www.palagems.com/Images/ruby_thai_1pt21cts.jpg
http://www.made-inchina.com/image/2f0j00yvmaMiBqfTgkM/Brown-Corundumfor-Abrasives-and-Refractories.jpg
http://www.gemeastcorporation.com/images/blue
http://sapphirerings.net/wp-content/uploads/2009/03/sapphirering.jpg
%20sapphire/star%20blue%20sapphire.jpg
Halides
ƒ
ƒ
ƒ
ƒ
Halogen ions, Cl-, Br-, F- and IPure ionic bonding
Relatively low hardness, high melting point
Excellent electrical conductivity in molten
state
– Halite (NaCl)
– Sylvite (KCl)
– Fluorite (CaF2)
– Cryolite (Na2AlF6)
http://skywalker.cochise.edu/wellerr/mineral/halite/6halite1069.jpg
http://www.arrowwoodminerals.com/files/TurtleFluorite01b.JPG
http://www.unseentourthailand.com/pgallery/datafiles/gallery/
large/gallery_20090515_cab33ee.jpg
http://webmineral.com/specimens/photos/Fluorite.jpg
Carbonates
ƒ Anionic (CO3)2ƒ React with acid “fizz”
ƒ 2H+ + CO3 Æ H2O + CO2
– Calcite (CaCO3)
– Dolomite (CaMg(CO3)2
– Malachite (Cu2CO3(OH)2
– Azurite (Cu3(CO3)2(OH)2
http://skywalker.cochise.edu/wellerr/minbis
/malachite/6bzb-malachite-bandedq6.jpg
http://gwydir.demon.co.uk/jo/minerals/pix/calcite5.jpg
http://www.cs.cmu.edu/~adg/images/minerals/carb/dolomite.jpg
http://www.bitsofearth.com/images/azurite-34640-1.jpg
Nitrates
ƒ Anionic (NO3)1– Niter (KNO3)
– Nitratite (NaNO3)
http://pics.manager.co.th/Images/551000008433508.JPEG
http://mail.vcharkarn.com/uploads/70/70325.jpg
Borates
ƒ Anionic (B4O7)2-, (B5O9)3- or (B6O11)4– Borax (Na2B4O7.10H2O)
http://z.about.com/d/chemistry/1/0/D/R/borax.jpg
http://food.truelife.com/content/Member/3806_3.jpg
Sulfates & Chromates
ƒ Anionic (SO4)2- and (CrO4)2– Gypsum (CaSO4.2H2O)
– Anhydrite (CaSO4)
– Barite (BaSO4)
– Crocoite (PbCrO4)
http://www.pitt.edu/~cejones/GeoImages/1Minerals/2Sedimentary
Mineralz/Gypsum_Halite/GypsumSelenite.JPG
http://csm.jmu.edu/MINERALS/minerals%5C+VaBarite.jpg
http://www.hkbullex.com/english/bookpic/20082291062681483.jpg
http://www.exceptionalminerals.com/TUC2007-251crocoiteKW91.jpg
Phosphates
ƒ Anionic (PO4)3-, (VO4)3- and (AsO4)3– Apatite (Ca5(PO4)3(F, Cl, OH)
– Monazite (Ce, La, Y, Th)PO4
– Turquoise (CuAl6(PO4)4(OH)8.4H2O)
http://www.healingcrystals.com/images/cards/Apatite.jpg
http://www.sbturquoise.com/images/kgmturquoise/Kingman-DkChks1-2in-800x.jpg
Tungstates and Molybdates
ƒ Anionic (WO4)2- and (MoO4)2– Scheelite (CaWO4)
– Wolframite (Fe,Mn)WO4
– Wulfenite (PbMoO4)
Scheelite (glow blue under UV-light)
http://www.thestarguide.com/images/scheelite_on_muscovite
_from_pingwu_sichuan_province__china_c96u.jpg
http://www.cfm-minerals.it/images/MineraliMiei/Wolframite334bis.jpg
Wulframite
Wulfrenite
http://csm.jmu.edu/MINERALS/minerals%5C+Wulfenite.jpg
http://www.buyrockbitsonline.com/bit_images/Tungsten%20carbide%20in
sert%20tricone%2030%20INCH%20NEW%20GTX-C3MPS03D.jpg
Tungsten carbide
Silicates
ƒ Anionic (Si:O) in various ratio
ƒ Dominant minerals in the Earth’s crust
ƒ 7 subclasses based on arrangement of SiO4 tetrahedra
–
–
–
–
–
–
Nesosilicates
Sorosilicates
Cyclosilicates
Inosilicates (Chain silicates)
Phyllosilicates (Sheet silicates)
Tectosilicates
Augite
(pyroxene)
Hornblende (amphibole)
http://upload.wikimedia.org/wikipedia/commons/9/92/Aktinolith_Finnland.JPG
Mica (Phyllosilicate)
http://www.esrf.eu/UsersAndScience/Experiments/CRG/BM26/SaxsWaxs/Sxwxsample/AboutMica/Images/mica_2
Quartz (Tectosilicate)
http://www.soskids.arkansas.gov/supportfiles/state_symbols/lg-photos/quartz.jpg
http://vibrate.files.wordpress.com/2007/09/amethyst-geode1.jpg