Aragonite
Image: “Jonathan Zander (<a href="//commons.wikimedia.org/wiki/User:Digon3" title="User:Digon3">Digon3</a>)" (CC BY-SA 3.0)
Mineral NameAragonite
Chemical FormulaCaCO3
Mohs Hardness3.5
Crystal Systemorthorhombic
Lustervitreous
Streak Colorwhite
Cleavagedistinct on {010}, poor on {110} and {011}
Fracturesubconchoidal to uneven
Specific Gravity2.95
Colorsreddish-orange, brown, white, yellow
Transparencytranslucent
Type LocalityMolina de Aragón, Spain
Mineral GroupCarbonates
Usescollector, jewelry (rarely), water filtration, industrial
Associated Mineralscalcite, gypsum, zeolites, celestine
Raritycommon
Description
This specimen displays a radiating cluster of pseudohexagonal, prismatic aragonite crystals, exhibiting a warm reddish-orange to brown hue.
Geological Context
Aragonite forms in various low-temperature environments, including sedimentary deposits, hot springs, caves (as speleothems), and within the shells and skeletons of marine organisms. It is a polymorph of calcite, stable at higher pressures and lower temperatures.
