Grossular is a calcium-aluminum garnet, chemically Ca3Al2 (SiO4) 3. Its name comes from a shade of green reminiscent of gooseberry - Ribes grossularia. It occurs in perfectly constrained crystals or in irregular grains, in granular to solid aggregates. It is usually green, yellow, pink, brown and red. It most often occurs in carbonate rocks on contact with granites and pegmatites. It is also abundant on alluvial rice fields.