Sample Set No. 3: Carbonates Galore!
|
Mineral |
Composition |
Crystal System |
Occurrence |
|
Witherite |
BaCO3 |
Orthorhombic |
Ore Gangue mineral, with sulfides |
|
Calcite (Several varieties provided) |
CaCO3 |
Hexagonal/ Rhombohedral |
Ubiquitous: Generally in Sedimentary or Metamorphic rocks |
|
Dolomite |
CaMg(CO3)2 |
Hexagonal/ Rhombohedral |
Typically in sedimentary or metamorphic rocks: usually forms via diagenesis of Calcite |
|
Rhodochrosite |
MnCO3 |
Hexagonal/ Rhombohedral |
With other Mn-bearing minerals: Rare! |
|
Siderite |
FeCO3 |
Hexagonal/ Rhombohedral |
Ore gangue mineral; can occur in metamorphic rocks |
|
Magnesite |
MgCO3 |
Hexagonal/ Rhombohedral |
Metamorphism of Mafic/ultramafic igneous rocks |
|
Strontianite |
SrCO3 |
Orthorhombic |
Ore Gangue mineral |
|
Aragonite |
CaCO3 |
Orthorhombic |
Evaporites; formed by corals and other carbonate-secreting creatures |
|
Malachite |
Cu2CO3(OH)2 |
Monoclinic |
Secondary Cu ore - typically found with azurite |
|
Azurite |
Cu 3(CO3)2(OH)2 |
Monoclinic |
Secondary Cu ore - Typically found with malachite |