Olivine Peridot Raw Minerals Stones Rocks Collecting

Description

Origin : Arizona (USA)

Olivine Peridot or Chrysolite 15-35 gr - cm 2.5-4 Raw Minerals Stones Rocks for Collection.

Olivine, Chrysolite or Peridot is a mineral belonging to the nesosilicates.
It is an isomorphic mixture of Forsterite (Mg2SiO4) and Fayalite (Fe2SiO4). The latter are rare in nature.
Olivines may contain manganese instead of iron and magnesium.
The name derives from the olive green color typical of this mineral. The term Chrysolite is used as a synonym when the stone appears transparent, while Peridot is a dated term that indicates a transparent variety, in particular a gem, of the mineral.
The structure of olivine is characterized by isolated tetrahedra of SiO4 linked by interstitial cations in octahedral coordination.
The crystalline habit occurs above all in a granular and massive form.
Olivines are fundamental constituents of many rocks, especially magmatic ones, both intrusive and effusive and represent the first mineral to crystallize from a melt originating from the partial fusion of the earth's mantle.
Olivine can also be a product of the metamorphism of ultrabasic metamorphic rocks (eg serpentinites) and sedimentary rocks such as impure limestones and dolomites.
The gem variety of olivine can be found in Burma, while in Arizona and New Mexico it occurs as rounded grains in association with pyroxenes in surface gravels. In Europe, the main source of olivine is Norway and about 50% of it circulating for industrial use in the world comes from this country. Widely present in the lava of Etna.
Olivine can also be found in areolites (meteorites mainly made up of silicates) and siderolites in the form of glassy granules.
Olivines melt at very high temperatures and are therefore used in various industrial processes. Peridot, on the other hand, is classified as a semi-precious stone and used in jewelry.