Garnet (2) Crystal Raw Minerals Stones Crystals Rocks Collecting

Description

Origin : China

Garnet Crystal 20-30 gr - cm 1.5-3 Raw Minerals Crystals Stones Rocks for Collection.

Garnets are a group of nesosilicate minerals. There are six main species of garnets, grouped into two isomorphic series (compounds having the same general formula and the same crystalline forms but with different chemical composition): pyralspite (pyrope, almandine, spessartine) and ugrandite (uvarovite, grossularia, andradite).
The name "garnet" derives from the Latin granatus (wheat), with a probable reference to mela granatum (pomegranate), a plant with red seeds with a shape and color similar to those of some garnet crystals.
Silicon is placed at the center of a tetrahedron with four oxygen atoms at the vertices; the latter are linked to cations thus constituting the structure of the garnets.
Garnets are found in various colors, varying according to composition, including red, orange, yellow, green, pink, purple, brown, black, and blue. There are also several varieties of garnets that change color as the light to which they are exposed varies.
Garnets have a vitreous or resinous luster, and are transparent or translucent.
Generally the crystals are well formed; also in rounded or fractured granules; also massive granular.
The crystalline habit is predominantly dodecahedral, trapezohedral (often in combination) occasionally the hexacisoctahedron is also observed; the crystal system is cubic.
Since ancient times, garnets have been commonly used as gemstones. Nowadays garnet sand is used for industrial purposes as a good abrasive. Mixed with very high pressure water, garnet is used to cut steel and other materials in water jets.