Olivine (Peridot)
Image: Dave Dyet <a rel="nofollow" class="external free" href="http://www.shutterstone.com">http://www.shutterstone.com</a> <a rel="nofollow" class="external free" href="http://www.dyet.com">http://www.dyet.com</a> (Public domain)
Mineral NameOlivine (Peridot)
Chemical Formula(Mg,Fe)₂SiO₄
Mohs Hardness6.5
Crystal Systemorthorhombic
Lustervitreous
Streak Colorwhite
Cleavagepoor on {010} and {100}
Fractureconchoidal
Specific Gravity3.34
Colorsyellowish-green, olive green, brownish-green
Transparencytransparent to translucent
Type LocalityJackson County, North Carolina
Mineral GroupSilicates
Usesjewelry, refractory material, industrial source of magnesium, collector
Associated Mineralspyroxene, chromite, magnetite, serpentine, spinel
Raritycommon
Description
A roughly triangular fragment of yellowish-green olivine, exhibiting a granular texture with some visible sparkle and a small reddish-brown inclusion.
Geological Context
Olivine is a primary mineral in mafic and ultramafic igneous rocks such as basalt, gabbro, and peridotite, crystallizing from magma at high temperatures and pressures deep within the Earth's mantle. It can also be found in some metamorphic rocks and meteorites.
