Geology and Minerals

Garnet

Garnets ( ) are a group of silicate minerals that have been used since the Bronze Age as gemstones and abrasives. Garnet minerals, while sharing similar physical and crystallographic properties, exhibit a wide range of chemical compositions, defining distinct species. These species fall into two primary solid solution series: the pyralspite series (pyrope, almandine, spessartine), with the general formula [Mg,Fe,Mn]3Al2(SiO4)3; and the ugrandite series (uvarovite, grossular, andradite), with the general formula Ca3[Cr,Al,Fe]2(SiO4)3. Notable varieties of grossular include hessonite and tsavorite. Although garnets are often associated with metamorphism, they can also occur in volcanic rocks on rare occasions.

Also on this shelf

See also

• ▸Iron ore
• ▸Algerian art
• ▸Carlin–type gold deposit

Uncatalogued shelf

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