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 on {1011}
Fractureconchoidal
Specific Gravity2.71
Colorswhite, pale grey
Transparencytranslucent
Type LocalityEgremond, Cumberland, UK
Mineral GroupCarbonates
Usesconstruction, industrial, optical, collector
Associated Mineralsquartz, fluorite, barite, pyrite
Raritycommon
Description
A translucent, pale white to light grey calcite crystal, exhibiting a distinct rhombohedral form and showing evidence of twinning, possibly a 'heart twin' as noted in the metadata.
Geological Context
Calcite is a ubiquitous mineral found in various geological settings, including sedimentary rocks (limestone, marble), hydrothermal veins, and as a secondary mineral in igneous and metamorphic rocks.
