Olivine
Image: Robert M. Lavinsky (CC BY-SA 3.0)
Mineral NameOlivine
Chemical Formula(Mg,Fe)₂SiO₄
Mohs Hardness6.5
Crystal Systemorthorhombic
Lustervitreous
Streak Colorwhite
Cleavagepoor/indistinct in two directions
Fractureconchoidal
Specific Gravity3.27
Colorsgreenish-yellow, olive green, yellow-green, brownish-green
Transparencytranslucent
Type LocalitySuppat, Kohistan, Pakistan
Mineral GroupSilicates (Nesosilicates)
Usesjewelry (as peridot), refractory material, industrial (source of magnesium)
Associated Mineralspyroxene, plagioclase, chromite, magnetite, serpentine
Raritycommon
Description
This specimen features a cluster of well-formed, translucent, lustrous, greenish-yellow olivine crystals, specifically the peridot variety. The largest crystal in this miniature specimen measures 4.0 cm in length.
Geological Context
Olivine is a primary mineral in mafic and ultramafic igneous rocks such as basalt, gabbro, peridotite, and dunite, forming at high temperatures and pressures. It is also a major component of the Earth's upper mantle and can be found in some metamorphic rocks and meteorites.
