Descriptive Mineralogy NonSilicates Carbonates Classification of the Minerals
Descriptive Mineralogy Non-Silicates: Carbonates
Classification of the Minerals • Non-Silicates – Native Elements – Halides – Sulfides – Carbonates – Sulfates – Phosphates – Oxides – Hydroxides • Silicates – Orthosilicates – Sorosilicates – Cyclosilicates – Chain Silicates – Layer Silicates – Tektosilicates
Carbonates • • Calcite Group Aragonite Group Dolomite Group Other carbonates
Carbonate Periodic Table
Calcite Group • • • Calcite Ca. CO 3 Magnesite Mg. CO 3 Siderite Fe. CO 3 Rhodochrosite Mn. CO 3 Smithsonite Zn. CO 3
Calcite Structure • Space Group R-3 c • Divalent cation radius < 1. 00Å
Calcite Ca. CO 3
Calcite Ca. CO 3 Occurrence: Sedimentary: Detrital and Evaporite limestones Metamorphic: Marble Low temperature hydrothermal. Igneous: Carbonatites, Kimberlites Uses: Building stone, Sculpture, Gravel and paving Acid mine drainage mitigation
Rhodochrosite Mn. CO 3 Occurrence: Low T Hydrothermal Uses: Mineral Specimens
Siderite Fe. CO 3 Occurrence: Low temperature hydrothermal. Use; Minor ore of Fe
Magnesite Mg. CO 3 Occurrence: olivine weathering Uses: Chalk CO 2 Sequestration?
Smithsonite Zn. CO 3 Occurrence: Oxidized Hydrothermal (after sphalerite) Uses: Minor ore of Zn
Aragonite Group • • Aragonite Ca. CO 3 Strontianite Ca. CO 3 Witherite Ba. CO 3 Cerussite Pb. CO 3
Aragonite Structure • Space Group Pbnm • Cation Radius > 1. 00Å
Aragonite Ca. CO 3 Occurrence: High pressure rocks Some shells Boiler scale Uses: None
Strontianite Sr. CO 3 Occurrence: Low T Hydrothermal Uses: Principal source of Sr (used in fireworks, ammunition, flares)
Witherite Ba. CO 3 Occurrence: Low T Hydrothermal Uses: Rat Poison
Witherite transforms at RT from orthorhombic to trigonal • Witherite (Ba. CO 3) • 0 GPa 8. 0 GPa
Cerussite Pb. CO 3 Occurrence: Oxidized Hydrothermal Uses: Minor ore of Pb
Dolomite Group • Dolomite Ca. Mg(CO 3)2 • Ankerite Ca. Fe(CO 3)2
Dolomite Ca. Mg(CO 3)2 Occurrence: Sedimentary, Igneous (carbonantites) Uses: None
Other Carbonates • • Malachite Cu 2(CO 3)(OH)2 Azurite Cu 3(CO 3)2(OH)2 Bastnasite Ce. CO 3 F Bastnasite REECO 3 F
Malachite Cu 2 CO 3(OH)2 Occurrence: Low T Hydrothermal Supergene Cu Uses: Minor ore of Cu, gems and ornaments
Azurite Cu 3(CO 3)2(OH)2 Occurrence: Low T Hydrothermal Supergene Cu Uses: Minor ore of Cu, gems and ornaments
Bastnasite Ce. CO 3 F Occurrence: Pegmatite Uses: Principal Source of Rare Earth Elements
Bastnasite Ce. CO 3 F
Carbonate Periodic Table
Gossans are Oxidized Hydrothermal Deposits
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