Peridotites

Peridotites: ultramafic intrusive igneous rocks with an holocrystalline autothomorphic structure (lacking a crystallization order), composed mainly of olivine and subordinately of Pyroxenes. When containing Biotite or Amphiboles, they are designated by the characteristic mineral’s name: Mica Peridotites, Amphibolitic Peridotites, etc. Most exposed Peridotites are altered into Serpentinites. They have a compact appearance and a dark green to black mottled color.

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