Dolomite
Image: Didier Descouens (CC BY-SA 4.0)
Mineral NameDolomite
Chemical FormulaCaMg(CO₃)₂
Mohs Hardness3.5
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavageperfect rhombohedral in three directions
Fractureconchoidal
Specific Gravity2.85
Colorswhite, cream, yellowish-brown
Transparencytranslucent
Type LocalityAzcárate Quarry, Eugui, Esteribar, Navarre, Spain
Mineral GroupCarbonates
Usesconstruction material, source of magnesium, soil conditioner, collector's specimens
Associated Mineralsmagnesite
Raritycommon
Description
A cluster of large, blocky, white to cream-colored rhombohedral dolomite crystals, some showing distinct growth patterns, growing over a base of smaller, yellowish-brown crystals, identified as magnesite.
Geological Context
Dolomite typically forms in sedimentary environments, often as a secondary mineral replacing limestone (dolomitization) or precipitating from hypersaline waters. It can also be found in hydrothermal veins.
