Spessartine is a nesosilicate, manganesealuminiumgarnet species, Mn2+3Al2(SiO4)3.[1][2][3][4] This mineral is sometimes mistakenly referred to as spessartite.[6]
Spessartine's name is a derivative of Spessart in Bavaria, Germany, the type locality of the mineral.[2][3] It occurs most often in granitepegmatite[2][3][4] and allied rock types and in certain low-grade metamorphicphyllites. Sources include Australia, Myanmar, India, Afghanistan, Israel, Madagascar, Namibia, Nigeria, Mozambique, Tanzania and the United States.[1] Spessartine of an orange-yellow has been called Mandarin garnet and is found in Madagascar. Violet-red spessartines are found in rhyolites in Colorado and Maine. In Madagascar, spessartines are exploited either in their bedrock or in alluvium. The orange garnets result from sodium-rich pegmatites. Spessartines are found in bedrock in the highlands in the Sahatany valley. Those in alluvium are generally found in southern Madagascar or in the Maevatanana region.[7][8][9][10][11]
Spessartine forms a solid solution series with the garnet species almandine.[3][4] Well-formed crystals from this series, varying in color from very dark-red to bright yellow-orange, were found in Latinka, Rhodope Mountains, Kardzhali Province, Bulgaria.[12] Spessartine, like the other garnets, always occurs as a blend with other species. Gems with high spessartine content tend toward a light orange hue, while almandine prevalence induces red or brownish hues.[13]
↑Shigley, James; Dona Dirlam; Brendan Laurs; Edward Boehm; George Bosshart; William Larson (2000). "Gem localities of the 1990s". Gems & Gemology36 (4): 292–335. doi:10.5741/GEMS.36.4.292.
↑Laurs, Brendan; Kimberly Knox (2001). "Spessartine garnet from Ramona, San Diego County, California". Gems & Gemology37 (4): 278–295. doi:10.5741/GEMS.37.4.278.
Spessartine on smoky quartz: Wushan Spessartine Mine, Tongbei, Fujian Province, China
Reddish-orange spessartine
Two "frog-eyes" of 1.8 cm each sit perched atop a matrix
