Calcite
Image: <a href="//commons.wikimedia.org/wiki/User:Archaeodontosaurus" title="User:Archaeodontosaurus">Didier Descouens</a> (CC BY-SA 3.0)
Mineral NameCalcite
Chemical FormulaCaCO3
Mohs Hardness3
Crystal Systemtrigonal
Lustervitreous
Streak Colorwhite
Cleavageperfect rhombohedral in three directions
Fractureconchoidal to uneven
Specific Gravity2.71
Colorswhite, colorless, brown, tan
Transparencytransparent
Type LocalityPau, Pyrénées-Atlantiques, Aquitaine, France
Mineral GroupCarbonates
Usesconstruction, agriculture, optical, chemical industry, collector
Associated Mineralsquartz, dolomite, fluorite, barite
Raritycommon
Description
This image displays a geode-like formation with a rough, earthy brown and tan exterior, revealing an interior cavity densely lined with numerous small, clear to white, translucent calcite crystals.
Geological Context
Calcite is a common mineral forming in diverse geological settings, including sedimentary rocks (limestone, marble), hydrothermal veins, and as a secondary mineral in geodes within sedimentary or volcanic rocks, often precipitating from aqueous solutions.
