Mineral Classification PDF
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These lecture notes provide an overview of mineral classes, including non-silicates such as native elements, oxides, sulfides, sulfosalts, and more. It categorizes minerals based on their chemical composition and internal structure. The notes also cover silicates, further detailing their various groups and properties.
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Lec 9: Mineral Classes Geol 103: Elementary Mineralogy Systematic mineralogy Identification and classification of minerals by their properties Lec 9: Mineral Classes Mineral classification basis Chemical composition: bas...
Lec 9: Mineral Classes Geol 103: Elementary Mineralogy Systematic mineralogy Identification and classification of minerals by their properties Lec 9: Mineral Classes Mineral classification basis Chemical composition: based on anion Internal structure Lec 9: Mineral Classes based on Mineral class anion based on Mineral family chemical type based on Mineral group structural similarity same Mineral species structure but presence of Mineral variety different chemistries unusual amounts of chemical constituents Lec 9: Mineral Classes Non- silicates Minerals that do not have a silica tetrahedron Lec 9: Mineral Classes Non- Silicate General Chemistry Native elements 1 element Sulfides Metal + sulfur Sulfosalt Metal + semi- metal Oxide Metal + oxygen Hydroxide Metal + OH or H2O Halide Metal + halogen Carbonate Metal + CO3 Sulfate Metal + SO4 Lec 9: Mineral Classes Other Non- Silicate General Chemistry Phosphate Metal + PO4 Arsenate Metal + AsO4 Vanadate Metal + VO4 Nitrate Metal + NO3 Borate Metal + BO3 Tungstate Metal + WO4 Molybdate Metal + MoO4 Lec 9: Mineral Classes Native elements General chemistry: 1 element Native metals, native semi- metals, native non- metals Lec 9: Mineral Classes Generally dense, soft, malleable, ductile, Native metals sectile, low melting points, metallic luster Groups: gold, iron, platinum Iron (Fe) Gold (Au) Silver (Ag) Platinum (Pt) Copper (Cu) Lec 9: Mineral Classes Sheeted structure Native semi- metals Generally brittle, poorer conductors of heat and electricity, good cleavage Arsenic (As) Bismuth (Bi) Lec 9: Mineral Classes Generally brittle, not malleable, poor Native non- metals heat and electricity conductor Sulfur (S) Graphite (C) Diamond (C) Lec 9: Mineral Classes Sulfides General chemistry: metal + sulfur Majority of ore minerals Generally opaque, distinct color, colored streaks Bonding: ionic, metallic, covalent Lec 9: Mineral Classes Orpiment (As2S3) Cinnabar (HgS) Galena (PbS) Sphalerite (ZnS) Realgar Bornite (AsS) (Cu5FeS4) Lec 9: Mineral Classes Covellite (CuS) Chalcocite (Cu2S) Chalcopyrite (CuFeS2) Pyrite (FeS2) Molybdenite (MoS2) Stibnite (Sb2S3) Lec 9: Mineral Classes Unoxidized sulfur mineral that is structurally Sulfosalt distinct from a sulfide Semi-metals take place of sulfur in the structure Considered as double sulfide Enargite Luzonite (Cu3AsS4) (Cu3AsS4) Lec 9: Mineral Classes Oxide General chemistry: metal + oxygen Strongly ionic bonding Great economic importance Generally hard, dense, refractory Group: hematite, rutile, spinel Lec 9: Mineral Classes Hematite (Fe2O3) Corundum (Al2O3) Rutile (TiO2) Chromite Ilmenite (FeCr2O4) (FeTiO3) Cuprite (Cu2O) Lec 9: Mineral Classes Pyrolusite Zincite Magnetite (MnO2) (ZnO) (Fe3O4) Lec 9: Mineral Classes Hydroxide General chemistry: metal + (OH)- or H2O Weaker bond strength than oxides Lower hardness and density Lec 9: Mineral Classes Goethite (αFeO(OH)) Manganite (MnO(OH)) Bauxite (mixture of Diaspore diaspore, gibbsite, (αAlO(OH)) boehmite) Lec 9: Mineral Classes Halides General chemistry: metal + halogen Highest possible symmetry Purely ionic bonding Generally low hardness, moderate to high melting points, poor heat and electricity conductor (in solid state) Lec 9: Mineral Classes Fluorite (CaF2) Sylvite (KCl) Halite (NaCl) Lec 9: Mineral Classes Carbonates General chemistry: metal + CO3 Strongly bonded units and do not share oxygen with each other Groups: calcite, aragonite, dolomite, monoclinic with (OH) 2H+ + CO3 → H2O + CO2 Lec 9: Mineral Classes Calcite Aragonite Dolomite (CaCO3) (CaCO3) (CaMg(CO3)2) Lec 9: Mineral Classes Azurite (Cu3(CO3)2(OH)2) Magnesite (MgCO3) Siderite (FeCO3) Rhodochrosite (MnCO3) Malachite (Cu2CO3(OH)2) Lec 9: Mineral Classes Sulfates General chemistry: metal + SO4 Anhydrous and hydrous sulfates Variable characteristics but may be soluble and fluorescent Common in evaporite environments Lec 9: Mineral Classes Barite (BaSO4) Anhydrite (CaSO4) Gypsum (CaSO4 2H2O) Lec 9: Mineral Classes Fundamental unit: SiO4 Silicates 25% of known minerals; 90% of earth’s crust Forms in various environments 45% 40% 35% 30% 25% 20% 39% 15% 10% 5% 12% 12% 11% 8% 5% 5% 5% 3% 0% Plagioclase Alkali Quartz Pyroxene Amphibole Mica Clay Other Non- feldspar silicates silicates Lec 9: Mineral Classes Silicate Group AKA Si-O Ratio Nesosilicate Island silicate 1:4 Sorosilicate Bowtie silicate 2:7 Cyclosilicate Ring silicate 1:3 Inosilicate Single chain silicate 1:3 Double chain silicate 4:11 Phyllosilicate Sheet silicate 2:5 Tectosilicate Framework silicate 1:2 Lec 9: Mineral Classes Nesosilicate Sorosilicate Cyclosilicate Lec 9: Mineral Classes Inosilicate Phyllosilicate Tectosilicate Lec 9: Mineral Classes Si- O ratio = 1:4 Nesosilicate Isolated SiO4 tetrahedra Island silicate Ionic bonding Generally high specific gravity, hard, equidimensional habit, no cleavage Groups: phenacite, olivine, garnet, zircon, Al2SiO5, humite Lec 9: Mineral Classes Garnet ((Ca, Mg, Fe, Mn)3(Al, Fe, Cr)2(SiO4)3) Zircon (ZrSiO4) Staurolite Olivine ((Mg, Fe)2 SiO4) Lec 9: Mineral Classes Kyanite Al2SiO5 polymorph Andalusite Sillimanite Lec 9: Mineral Classes Si- O ratio = 2:7 Sorosilicate 1 corner oxygen is shared Double island silicate Group: epidote Epidote Lec 9: Mineral Classes Cyclosilicate Si- O ratio = 1:3 2 oxygens are shared Ring silicate Beryl (Be3Al2(Si6O18)) Tourmaline Lec 9: Mineral Classes Inosilicate Single/ double chain silicate Single chain Si- O ratio= 1:3 Double chain Si- O ratio= 4:11 Groups: pyroxene (single), amphibole (double) Generally green to black color, hard, vitreous Lec 9: Mineral Classes Pyroxene Amphibole Lec 9: Mineral Classes Phyllosilicate Sheet silicate Si:O ratio= 2:5 Generally platy or flaky habit, 1 distinct cleavage, soft, low specific gravity, flexible, elastic Group: serpentine, clay mineral, mica, chlorite Lec 9: Mineral Classes Kaolinite Muscovite Talc Biotite Chlorite Lec 9: Mineral Classes Serpentine Lec 9: Mineral Classes Tectosilicate Framework silicate Si- O ratio= 1:2 All oxygen are shared Stable, strongly bonded structure Groups: SiO2, feldspar (k- feldspar, plagioclase feldspar), feldspathoid, scapolite, zeolite Lec 9: Mineral Classes Quartz (SiO2) Lec 9: Mineral Classes Orthoclase Lazurite (KAlSi3O8) Plagioclase feldspar ((Ca, Na) AlSi3O8) Lec 9: Mineral Classes