How do I identify Ferrosilite?

Ferrosilite can be identified by its hardness of 5 - 6 on the Mohs scale, Dark brown to black color. Look for these key characteristics when examining specimens.

What color is Ferrosilite?

Ferrosilite typically appears in Dark brown to black. Color can vary depending on impurities and formation conditions.

How hard is Ferrosilite?

Ferrosilite has a hardness of 5 - 6 on the Mohs scale. This gives it moderate hardness.

Ferrosilite

A variety of Orthopyroxene Subgroup

What is Ferrosilite?

Enstatite is a mineral; the magnesium endmember of the pyroxene silicate mineral series enstatite (MgSiO3) – ferrosilite (FeSiO3). The magnesium rich members of the solid solution series are common rock-forming minerals found in igneous and metamorphic rocks. The intermediate composition, (Mg,Fe)SiO3, has historically been known as hypersthene, although this name has been formally abandoned and replaced by orthopyroxene. When determined petrographically or chemically the composition is given as relative proportions of enstatite (En) and ferrosilite (Fs) (e.g., En80Fs20).

Ferrosilite Market Value Calculator

Estimate the market value of Ferrosilite using size, quality, and finish. This preview calculator is for quick context and is not a formal appraisal.

Ferrosilite Localities Map

See where Ferrosilite is found with a localities map, collecting zones, and geology context. Generate a sample map preview below.

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North ZoneCentral RidgeSouth Basin

Key Characteristics

Formation of Ferrosilite

Isolated crystals are rare, but orthopyroxene is an essential constituent of various types of igneous rocks and metamorphic rocks. Magnesian orthopyroxene occurs in plutonic rocks such as gabbro (norite) and diorite. It may form small idiomorphic phenocrysts and also groundmass grains in volcanic rocks such as basalt, andesite, and dacite. Enstatite, close to En90Fs10 in composition, is an essential mineral in typical peridotite and pyroxenite of the Earth's mantle. Xenoliths of peridotite are common in kimberlite and in some basalt. Measurements of the calcium, aluminum, and chromium contents of enstatite in these xenoliths have been crucial in reconstructing the depths from which the xenoliths were plucked by the ascending magmas. Orthopyroxene is an important constituent of some metamorphic rocks such as granulite. Orthopyroxene near pure enstatite in composition occurs in some metamorphosed serpentines. Large crystals, a foot in length and mostly altered to steatite, were found in 1874 in the apatite veins traversing mica-schist and hornblende-schist at the apatite mine of Kjørstad, near Brevik in southern Norway. Enstatite is a common mineral in meteorites. Crystals have been found in stony and iron meteorites, including one that fell at Breitenbach in the Ore Mountains, Bohemia. In some meteorites, together with olivine it forms the bulk of the material; it can occur in small spherical masses, or chondrules, with an internal radiated structure.