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Manganoeudialyte
Manganoeudialyte is an moderately rare mineral of the eudialyte group,Mindat, Manganoeudialyte, http://www.mindat.org/min-39640.html with formula Na14Ca6Mn3Zr3Si2[Si24O72(OH)2]Cl2·4H2O. The formula given is one of the forms that can be given, based on the originally reported one, and shows dominance of silicon at both the M3 and M4 sites. As suggested by its name, it is the manganese-analogue of eudialyte.Nomura, S.F., Atencio, D., Chukanov, N.V., Rastsvetaeva, R.K., Coutinho, J.M.V., and Karipidis, T.K., 2010: Manganoeudialyte – a new mineral from Poços de Caldas, Minas Gerais, Brasil. Zapisko RMO 4Handbook of Mineralogy, Manganoeudialyte, http://www.handbookofmineralogy.org/pdfs/manganoeudialyte.pdf Occurrence and association Manganoeudialyte was discovered in khibinites of the Poços de Caldas massif, Brazil. Associated minerals are aegirine, analcime, astrophyllite, cancrinite, fluorite, lamprophyllite, nepheline, potassium feldspar, rinkite, sodalite, and titanite. Notes o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eudialyte Group
Eudialyte group is a group of complex trigonal zircono- and, more rarely, titanosilicate minerals with general formula (1)N(2)N(3)N(4)N(5)sub>3 (1a)M(1b)sub>3M(2)3M(4)Z3 i24O72'4X2, where N(1) and N(2) and N(3) and N(5) = Na+ and more rarely H3O+ or H2O, N(4) = Na+, Sr2+, Mn2+ and more rarely H3O+ or H2O or K+ or Ca2+ or REE3+ (rare earth elements), M(1) and M(1b) = Ca2+, M(1a) = Ca2+ or Mn2+ or Fe2+, M(2) = Fe (both II and III), Mn and rarely Na+, K+ or Zr4+, M(3) = Si, Nb and rarely W, Ti and [] (vacancy defect, vacancy), M(4) = Si and or rarely [], Z Zr4+ and or rarely Ti4+, and X = OH−, Cl− and more rarely CO32− or F−. Some of the eudialyte-like structures can even be more complex, however, in general, its typical feature is the presence of i3O9sup>6− and i9O27sup>18− ring silicate groups. Space group is usually ''R''3''m'' or ''R''-3''m'' but may be reduced to ''R''3 due to cation ordering. Like other zirconosilicates, the eudialyte group minerals pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |