Image: James St. John (CC BY 2.0)
trigonalcommonCarbonates
Calcite
CaCO3
The image displays well-formed, transparent to translucent, colorless to white calcite crystals exhibiting characteristic rhombohedral forms.
Calcite Physical Properties
Mohs Hardness
3Crystal System
trigonalLuster
vitreousStreak Color
whiteCleavage
Perfect rhombohedral in three directions at 74° 55'Fracture
conchoidalSpecific Gravity
2.71Colors
white, clear, yellow, pink, blue, green, brown, blackTransparency
transparentType Locality
Pugh Quarry, near Custar, Ohio, USAMineral Group
CarbonatesUses
cement production, flux in metallurgy, soil conditioner, optical instruments (Iceland spar), building material, acid neutralizationAssociated Minerals
quartz, fluorite, barite, pyrite, galena, sphaleriteRarity
commonGeological Context
Calcite is a very common mineral found in various geological settings, including sedimentary rocks (limestone, marble), hydrothermal veins, and as a secondary mineral in igneous and metamorphic rocks. It forms from the precipitation of calcium carbonate from aqueous solutions.
