page_title: Garnet
section_title: Grossular
hierarchical_section_title: Garnet / Garnet group end member species / Ugrandite group – calcium in X site / Grossular
caption_attribution_description: English: Grossular garnet from Quebec, collected by Dr John Hunter in the 18th century, Hunterian Museum, Glasgow
context_page_description: Garnets are a group of silicate minerals that have been used since the Bronze Age as gemstones and abrasives.
  All species of garnets possess similar physical properties and crystal forms, but differ in chemical composition. The different species are pyrope, almandine, spessartine, grossular, uvarovite and andradite. The garnets make up two solid solution series: pyrope-almandine-spessartine and uvarovite-grossular-andradite.
context_section_description: Grossular is a calcium-aluminium garnet with the formula Ca₃Al₂(SiO₄)₃, though the calcium may in part be replaced by ferrous iron and the aluminium by ferric iron. The name grossular is derived from the botanical name for the gooseberry, grossularia, in reference to the green garnet of this composition that is found in Siberia. Other shades include cinnamon brown (cinnamon stone variety), red, and yellow. Because of its inferior hardness to zircon, which the yellow crystals resemble, they have also been called hessonite from the Greek meaning inferior. Grossular is found in skarns, contact metamorphosed limestones with vesuvianite, diopside, wollastonite and wernerite.
  Grossular garnet from Kenya and Tanzania has been called tsavorite. Tsavorite was first described in the 1960s in the Tsavo area of Kenya, from which the gem takes its name.
caption: Grossular garnet from Quebec, collected by Dr John Hunter in the 18th century, Hunterian Museum, Glasgow
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