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Chapter 3 Nonsilicate Minerals the 8 Most Common Elements in the Continental Crust Elements That Comprise Most Minerals Classification of Minerals

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Chapter 3 Nonsilicate Minerals the 8 Most Common Elements in the Continental Crust Elements That Comprise Most Minerals Classification of Minerals Chapter 3 Nonsilicate Minerals The 8 Most Common Elements in the Continental Crust Elements That Comprise Most Minerals Classification of Minerals ! "Important nonsilicate minerals •" Several major groups exist including –"Oxides –"Sulfides –"Sulfates –"Native Elements –"Carbonates –"Halides –"Phosphates Classification of Minerals ! "Important nonsilicate minerals •" Many nonsilicate minerals have economic value •" Examples –"Hematite (oxide mined for iron ore) –"Halite (halide mined for salt) –"Sphalerite (sulfide mined for zinc ore) –"Native Copper (native element mined for copper) Table 3.2 (Modified) Common Nonsilicate Mineral Groups Classification of Minerals ! "Important nonsilicate minerals •" Oxides – natural compounds in which Oxygen anions combine w/ a variety of metal cations –"Ores of various metals –"Hematite & Magnetite (iron oxides), Chromite (iron-chromium oxide), Ilmenite (iron-titanium oxide) and Ice (H2O – the solid form of water) are some important oxides Hematite (Fe2O3) Ore of Iron Red Streak Metallic to Earthy Luster Black or Red Color Magnetite (Fe3O4) Ore of Iron Strong Magnetism Black Color Hardness (6) Metallic Luster Corundum (Ruby& Sapphire) (Al2O3) Gemstone Hardness = 9 (Scratches Knife), Hexagonal Crystals, Adamantine Luster, Color Variable, But Can Be Red (Ruby) or Blue (Sapphire) Chromite (FeCr2O4) Ore of Chromium Metallic to Submetallic Luster Iron Black to Brownish Black Color Octahedral Crystal Form Hardness (5.5-6) Ilmenite (FeTiO3) Ore of Titanium Black-Brownish Black Streak Metallic to Submetallic Luster Black Color Table 3.2 (Modified) Common Nonsilicate Mineral Groups Classification of Minerals ! "Important nonsilicate minerals •" Sulfides – natural compounds in which Sulfur anions combine w/ a variety of metal cations –"Majority of the ore minerals –"Galena (lead sulfide), Sphalerite (zinc sulfide), Pyrite (iron sulfide), Chalcopyrite & Bornite (copper-iron sulfides) and Cinnabar (mercury sulfide) are some important sulfides Galena (PbS) Ore of Lead & Silver Cubic Cleavage Metallic Luster Heavy (SG=7.4-7.6) Soft (H=2.5) Lead-Gray Streak & Color Sphalerite (ZnS) Primary Ore of Zinc Resinous Luster, Crystal Forms = Tetrahedron, Dodecahedron, Cube Perfect Cleavage Reddish-Brown Streak Pyrite (FeS2) Sulfur for Sulfuric Acid Brass Yellow Color Metallic Luster, Hardness (6-6.5) Crystal Fm = Pyritohedrons, Cubes, Octahedrons Chalcopyrite (CuFeS2) Ore of Copper Brass Yellow Color, Metallic Luster, Tetrahedral Crystal Form, Green-Black Streak, Hardness (3.5-4) Brittle Bornite (Cu5FeS4) Ore of Copper Iridescent Blue, Purple or Copper-Red Color, Metallic Luster, Dark Gray Streak, Hardness (3) Cinnabar (HgS) Ore of Mercury Red Color Scarlet Streak Heavy (SG=8.1) Rhombohedral or Hexagonal Crystal Form Table 3.2 (Modified) Common Nonsilicate Mineral Groups Classification of Minerals ! "Important nonsilicate minerals •" Sulfates – natural compounds in which Sulfur+Oxygen anions combine w/ a variety of metal cations –"Used in construction & drilling mud –"Gypsum (hydrated calcium sulfate), Anhydrite (calcium sulfate), and Barite (barium sulfate) are some important sulfates Gypsum (CaSO4+2H2O) Plaster of Paris, Drywall & Fertilizer Soft (H=2), Three Unequal Cleavages, Vitreous–Pearly Luster, Tabular, Bladed, Prismatic or Needle Crystal Forms Anhydrite (CaSO4) Soil Conditioner & Cement Three Right Angle Cleavages, Soft (H=3-3.5) Barite (BaSO4) Drilling Mud Heavy (SG=4.5), Two Cleavages, Tabular Crystal Form, Hardness (3-3.5) Table 3.2 (Modified) Common Nonsilicate Mineral Groups Classification of Minerals ! "Important nonsilicate minerals •" Native Elements – Some elements can occur alone, not combined w/ other elements or compounds –"Native elements include both metals & nonmetals –"Gold, Silver, Copper & Platinum are some of the common metal elements; Diamond, Sulfur and Graphite are some of the more common nonmetal elements Gold (Au) Trade (Money) & Jewelry Gold Color, Heavy (SG=15-19), Malleable /Ductile, Metallic Luster Copper (Cu) Electrical Wiring & Alloys Copper Color, Heavy (SG=8.9), Malleable /Ductile, Metallic Luster Diamond (C) Gemstone Hardness = 10 (Hardest Known Mineral), Adamantine Luster Sulfur (S) Sulfa Drugs & Chemicals Yellow Color & Streak Conchoidal Fracture, Burns Readily, Smells Like Eggs Platinum (Pt) Catalyst, Dentistry, Jewelry, Electronics Steel-Gray Color Heavy (SG=14-21) Malleable Silver (Ag) Photo Film, Tableware, Electronics Silver Color, Heavy (SG=10-12), Malleable /Ductile, Metallic Luster Graphite (C) Refractory Crucibles, Lubricant, Pencil Lead, Paint Black Color & Streak Greasy Feel Readily Marks Paper & Fingers Hardness (1) Table 3.2 (Modified) Common Nonsilicate Mineral Groups Classification of Minerals ! "Important nonsilicate minerals •" Halides – Halogen Anions (Cl, Br, F, or I) + various cations –"Minerals in this group are often water soluble w/ a salty taste –"Halite (sodium chloride – talbe salt), Sylvite (potassium chloride) and Fluorite (calcium fluoride) are the most important halide minerals Halite (NaCl) Table Salt Cubic Cleavage & Crystal Form, Salty Taste, Dissolves in Water, Soft (2.50) Fluorite (CaF2) Catalyst in Steelmaking Cubic Crystals, Octahedral Cleavage, Hardness=4 (Scratch w/ Knife) Fluorite (CaF2) Catalyst in Steelmaking Cubic Crystals, Octahedral Cleavage, Hardness=4 (Scratch w/ Knife) Sylvite (KCl) Fertilizer Cubic Cleavage Bitter Salty Taste Readily Dissolves in Water Table 3.2 (Modified) Common Nonsilicate Mineral Groups Classification of Minerals ! " Important nonsilicate minerals •" Carbonates = CO3 Anion Radical + various cations –" Primary constituents in limestone and dolostone –" Calcite (calcium carbonate) and Dolomite (calcium- magnesium carbonate) are the two most important carbonate minerals –" Other important carbonates include Aragonite (calcium carbonate) and Azurite & Malachite (copper- bearing carbonates) Calcite (CaCO3) Portland Cement, Lime, Antacid Effervesces Strongly in Dilute HCl Rhombohedral Cleavage Hardness (3) Hexagonal Crystals Aragonite (CaCO3) Common in Warm Sea Water Effervesces Strongly in Dilute HCl, Elongate Crystals w/ Points or Blunt Terminations, Hardness = 3 (Scratch w/ Knife) Dolomite [CaMg(CO3)2] Portland Cement & Lime, Magnesium Ore, Soft Abrasive Effervesces Slowly in Dilute HCl, Rhombohedral Cleavage & Crystal Form, Hardness = 3.5-4 (Scratch w/ Knife) Malachite [Cu2CO3(OH)2] Gemstone Bright Green Color & Streak, Effervesces in Dilute HCl, Botryoidal Masses, Hardness (3.5-4) Azurite [Cu3(CO3)2(OH)2] Gemstone & Copper Ore Azure-Blue Color, Light Blue Streak, Effervesces in Dilute HCl, Prismatic Crystal Form or Opaque Earthy Masses, Hardness (3.5-4) Table 3.2 (Modified) Common Nonsilicate Mineral Groups Classification of Minerals ! "Important nonsilicate minerals •" Hydroxides = O+H Anions + various cations and H2O (Water) –"Low Grade Ores of Various Metals –"Limonite (iron hydroxide w/ water) and Bauxite (aluminium hydroxide w/ water) are the two most important hydroxide minerals . Limonite FeO(OH) nH2O Ore of Iron & Yellow Pigment Yellowish Brown Color & Streak, Hardness (1.5-5.5), Luster Dull to Earthy . Bauxite Al(OH)3 nH2O Ore of Aluminum Pisolitic Structure (contains rounded grains), Hardness (1-3), Luster Nonmetallic (Dull to Earthy), Color = White, Gray, Yellow, Red Table 3.2 (Modified) Common Nonsilicate Mineral Groups Classification of Minerals ! "Important nonsilicate minerals •" Phosphates = PO4 Anions + various cations –"Commonly used in or added to fertilizers –"Apatite (calcium phosphate) and Turquoise (copper-aluminium phosphate) are two common phosphate minerals Apatite [Ca5(PO4)3(F, Cl, OH)] Fertilizer Hexagonal Prismatic Crystals, Hardness = 5, Conchoidal Fracture . Turquoise [CuAl6(PO4)4(OH)8 5H2O] Gemstone Turquoise Blue Color, Hardness = 3.5-4 (Scratched w/ Knife) Precious Gemstones Clockwise from upper right = OPAL, SAPPHIRE, RUBY, EMERALD, DIAMOND (the famous HOPE blue diamond, surrounded by white diamonds) Semiprecious Gemstones Clockwise from upper right = ALEXANDRITE, AMETHYST, BLUE CHALCEDONY, CAT’S EYE (CHRYSOBERYL), CITRINE Semiprecious Gemstones Clockwise from upper right = GARNET, JADE, MOONSTONE (FELDSPAR), PERIDOTE (OLIVINE), SMOKY QUARTZ Semiprecious Gemstones Clockwise from upper right = SPINEL, TOPAZ, TOURMALINE, ZIRCON, TURQUOISE Estimated percentage (by volume) of the most common minerals in Earth’s crust .
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