Image: <bdi><a href="https://www.wikidata.org/wiki/Q56247090" class="extiw" title="d:Q56247090"><span title="mineral collector and dealer">Robert M. Lavinsky</span></a></bdi> (CC BY-SA 3.0)
orthorhombicuncommonCarbonates
Aragonite
CaCO₃
This specimen displays a beautiful cluster of radiating, acicular (needle-like) crystals of pale yellow to white aragonite, forming a botryoidal or stalactitic aggregate.
Aragonite Physical Properties
Mohs Hardness
3.5Crystal System
orthorhombicLuster
vitreousStreak Color
whiteCleavage
distinct on {010}, indistinct on {110} and {011}Fracture
subconchoidalSpecific Gravity
2.95Colors
white, colorless, gray, yellow, green, blue, violet, brown, pinkTransparency
transparent to translucentType Locality
Tsumeb, Otjikoto (Oshikoto) Region, NamibiaMineral Group
CarbonatesUses
collector, jewelry (rarely), industrial (cement, lime, agriculture)Associated Minerals
calcite, gypsum, malachite, azurite, smithsonite, hemimorphiteRarity
uncommonGeological Context
Aragonite is a polymorph of calcite, typically forming at lower temperatures and higher pressures, or in specific aqueous environments such as hot springs, caves (as speleothems), and mollusk shells. It can also occur in metamorphic and sedimentary rocks.
