Spessartine(redirected from spessartines)
(from the Spessart range in the Federal Republic of Germany), a mineral of the garnet group, a manganese-containing aluminogarnet having the composition Mn3AI2[SiO4]3 and containing typical isomorphic impurities of Fe2+, Mg2+, Ca2+, and Y3+. Spessartine crystallizes in the cubic system, forming crystals typical of garnets or, frequently, compact granular masses. The color varies, depending on impurities, from light pink to red-brown. The mineral has a hardness on Mohs’ scale of 7–7.5 and a density of 3,800–4,280 kg/m3. Spessartine is most commonly encountered in garnet pegmatites, metamorphic rocks, and skarns.