Calcite
Image: <a rel="nofollow" class="external text" href="https://www.flickr.com/people/25326737@N00">Jarno</a> from Rotterdam, Netherlands (CC BY 2.0)
Mineral NameCalcite
Chemical FormulaCaCO3
Mohs Hardness3
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavageperfect rhombohedral in three directions
Fractureconchoidal
Specific Gravity2.71
Colorsgreen, brown
Transparencytranslucent
Type LocalityMexico
Mineral GroupCarbonates
Usesconstruction, optical, soil treatment, collector
Associated Mineralsquartz, fluorite, pyrite, galena
Raritycommon
Description
A rough, translucent mass of green calcite, exhibiting some internal brownish inclusions and a glassy luster on its surfaces.
Geological Context
Calcite is a ubiquitous mineral, forming in diverse geological settings including sedimentary rocks (limestone, marble), hydrothermal veins, and as a secondary mineral in igneous and metamorphic rocks.
