Aragonite
Aragonite is a carbonate mineral, one of the two common, naturally occurring polymorphs of calcium carbonate, CaCO3. The other polymorph is the mineral calcite. Aragonite’s crystal lattice differs from that of calcite, resulting in a different crystal shape, an orthorhombic system with acicular crystals. Repeated twinning results in pseudo-hexagonal forms.
Type
Mineral
Mineral Classification
Carbonate
Chemical Formula
CaCO3
Streak
White
Mohs Hardness
3.5-4
Crystal System
Orthorhombic
Color
White, red, yellow, orange, green, purple, grey, blue and brown
Luster
Vitreous, resinous on fracture surfaces
Fracture
Subconchoidal
Description
Aragonite is a carbonate mineral, one of the two common, naturally occurring polymorphs of calcium carbonate, CaCO3. The other polymorph is the mineral calcite. Aragonite’s crystal lattice differs from that of calcite, resulting in a different crystal shape, an orthorhombic system with acicular crystals. Repeated twinning results in pseudo-hexagonal forms.
