Nesosilicate, manganese aluminium garnet species

Spessartine is a nesosilicate, manganese aluminium garnet species, Mn2+3Al2(SiO4)3.[2][3][4][5] 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.[3][4] It occurs most often in granite pegmatite[3][4][5] and allied rock types and in certain low-grade metamorphic phyllites. Sources include Australia, Myanmar, India, Afghanistan, Israel, Madagascar, Namibia, Nigeria, Mozambique, Tanzania and the United States.[2] 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.[4][5] 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]

Images

See also

References

  1. ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
  2. ^ a b c Gemological Institute of America, GIA Gem Reference Guide 1995, ISBN 0-87311-019-6
  3. ^ a b c d Webmineral Spessartine page
  4. ^ a b c d e Mindat Spessartine page
  5. ^ a b c d Handbook of Mineralogy Spessartine page
  6. ^ International Mineralogical Association (1971). "International Mineralogical Association: Commission on new minerals and mineral names" (PDF). Mineralogical Magazine. 38 (293): 102–105. Bibcode:1971MinM...38..102.. doi:10.1180/minmag.1971.038.293.14.
  7. ^ "Gem News". Gems & Gemology. 34 (1): 50–63. 1998-04-01. doi:10.5741/GEMS.34.1.50.
  8. ^ Shigley, James; Dona Dirlam; Brendan Laurs; Edward Boehm; George Bosshart; William Larson (2000). "Gem localities of the 1990s". Gems & Gemology. 36 (4): 292–335. doi:10.5741/GEMS.36.4.292.
  9. ^ Laurs, Brendan; Kimberly Knox (2001). "Spessartine garnet from Ramona, San Diego County, California". Gems & Gemology. 37 (4): 278–295. doi:10.5741/GEMS.37.4.278.
  10. ^ Rossman, George R. (2009). "The geochemistry of gems and its relevance to gemology: different traces, different prices". Elements. 5 (3): 159–162. doi:10.2113/gselements.5.3.159. ISSN 1811-5209.
  11. ^ Schmetzer, Karl; Thomas Hainschwang; Lore Kiefert; Heinz-Jürgen Bernhardt (2001). "Pink to pinkish orange Malaya garnets from Bekily, Madagascar". Gems & Gemology. 37 (4): 296–308. doi:10.5741/GEMS.37.4.296.
  12. ^ "Spessartine from Latinka, Bulgaria".
  13. ^ Spessartite Garnet Gemological Information

External links

Media related to Spessartine at Wikimedia Commons