igneous
Olivine Peridotite
Peridotite (comprising Olivine (Mg,Fe)2SiO4 and Pyroxene)
Hardness: 6.5-7 (Mohs); Color: Olive green to darker brownish-green; Luster: Vitreous to oily; Crystal Structure: Orthorhombic; Specific Gravity: 3.2-4.4.
- Hardness
- 6
- Color
- Olive green to darker brownish-green
- Luster
- Vitreous to oily
Identified More igneous →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7 (Mohs); Color: Olive green to darker brownish-green; Luster: Vitreous to oily; Crystal Structure: Orthorhombic; Specific Gravity: 3.2-4.4.
Formation & geological history
Formed deep within the Earth's mantle through fractional crystallization of ultramafic magma. They are brought to the surface via tectonic activity or volcanic eruptions as xenoliths.
Uses & applications
Primary source of the gemstone Peridot; used in industrial refractory materials due to high melting points and as a decorative stone in construction.
Geological facts
Peridotite is believed to be the dominant rock type of the upper mantle. Rare meteorites known as pallasites also contain crystals of olivine identical to those found in these rocks.
Field identification & locations
Identified by its distinctive olive-green color and heavy weight. Commonly found in ophiolites, volcanic pipes (kimberlites), and as basalt-hosted xenoliths at tectonic plate boundaries.
More like this
Other igneous specimens
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Dark Igneous Rock (Likely Basalt or Diabase)
Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.
Igneous
Magnetite
Iron(II,III) oxide (Fe3O4)
mineral
Sodalite
Sodalite - Na8(Al6Si6O24)Cl2
mineral
Blue Apatite
Apatite (Group), Ca5(PO4)3(F,Cl,OH)
mineral
Magnetite
Magnetite (Fe3O4)
mineral