igneous
Olivine (Peridotite)
(Mg,Fe)2SiO4 (Magnesium Iron Silicate)
Hardness: 6.5–7 on Mohs scale; Color: olive-green to yellowish-green; Luster: vitreous; Crystal system: orthorhombic; Specific gravity: 3.27–4.37.
- Hardness
- 6
- Color
- olive-green to yellowish-green
- Luster
- vitreous
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Physical properties
Hardness: 6.5–7 on Mohs scale; Color: olive-green to yellowish-green; Luster: vitreous; Crystal system: orthorhombic; Specific gravity: 3.27–4.37.
Formation & geological history
Formed in the Earth's upper mantle through slow cooling of magma at high temperatures. It is a primary constituent of the upper mantle and is often brought to the surface in basaltic lava or as xenoliths.
Uses & applications
Used as an industrial abrasive, a refractory material for casting molds, and as a gemstone (Peridot) in jewelry. It is also used in carbon sequestration research.
Geological facts
Olivine is one of the most common minerals on Earth by volume because it makes up much of the mantle. It has also been discovered in meteorites and on the Moon and Mars.
Field identification & locations
Look for a distinct 'sugary' or granular texture with a characteristic olive-green color. It is common in mafic and ultramafic volcanic rocks like basalt. Field ID involves checking for its high hardness and lack of cleavage.
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