- Calcite - CaCO , H = 3 , 3 rhombohedral cleavage planes at 75o , effervesces win HCl is applied , rhombohedral habit , white streak , white to colorless or tinted , vitreous to earthy luster , specific gravity = 2.71
- Siderite - FeCO , chocolate-brown color , H = 3.5 to 4 , rhombohedral crystals with curved faces , specific gravity = 3.96 , white streak , 1 perfect cleavage , vitreous luster
- Rhodochrosite - MnCO , pink color , H = 3.5 to 4 (*which is softer than rhodonite which is sometimes confused with it ), rhombohedral habit , white streak , perfect rhombohedral cleavage , vitreous luster
- Smithsonite - ZnCO , small crystalline crusts , H = 4 to 4.5 , brown to green-blue color , specific gravity 4.3 to 4.45 , white streak , vitreous luster , secondary mineral , occurs with other zinc minerals
Aragonite Group
- Aragonite - CaCO , acicular to prismatic habit , reacts to HCl , H = 3.5 to 4 harder than calcite , higher specific gravity than calcite S.G. = 2.94, white streak , color varies from colorless to white to tinted , 1 poor and 1 distinct cleavage , vitreous luster , *because of the difference in hardness between calcite and aragonite...the aragonite should scratch calcite not vice versa
- Strontianite - SrCO , white color , acicular radiating habit , reacts with HCl , poor cleavage , high specific gravity 3.78 , H = 3.5 to 4 , vitreous luster ; color varies from yellow to green to grey
- Cerrusite - PbCO , white color , high specific gravity 6.6 unusual for a light-colored mineral , association with galena (PbS) , white streak , H = 3 to 3.5 , weathering product of galena , 1 fair and 1 good cleavage , adamantine luster , stubby to tabular habit
Dolomite Group
- Dolomite - CaMg(CO) , when powdered the mineral reacts with HCl , curved rhombohedral crystals , vitreous luster , H = 3.5 to 4 , white streak ; various colors usually some shade of pink , white , or flesh color
Various Odd Carbonates
- Malachite - Cu(CO)(OH) , bright green color , radiating fibers - layered - botryoidal , reaction with HCl , association with other copper minerals , pale green streak , H = 3.5 to 4 , specific gravity = 3.9 to 4.3 , vitreous to adamantine luster
- Azurite - Cu(CO)(OH) , bright azure blue color , reaction HCl , association with other copper minerals especially malachite , pale blue streak , H = 3.5 to 4 , vitreous luster , 1 perfect and 1 fair cleavage , specific gravity = 3.77 , elongate tabular as a film or granular
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