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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] |
Trigonal
In crystallography, the hexagonal crystal family is one of the six crystal families, which includes two crystal systems (hexagonal and trigonal) and two lattice systems (hexagonal and rhombohedral). While commonly confused, the trigonal crystal system and the rhombohedral lattice system are not equivalent (see section crystal systems below). In particular, there are crystals that have trigonal symmetry but belong to the hexagonal lattice (such as α-quartz). The hexagonal crystal family consists of the 12 point groups such that at least one of their space groups has the hexagonal lattice as underlying lattice, and is the union of the hexagonal crystal system and the trigonal crystal system. There are 52 space groups associated with it, which are exactly those whose Bravais lattice is either hexagonal or rhombohedral. __TOC__ Lattice systems The hexagonal crystal family consists of two lattice systems: hexagonal and rhombohedral. Each lattice system consists of one Bravais l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alluaivite
Alluaivite is a rare mineral of the eudialyte group,http://www.mindat.org/show.php?id=141&ld=2 Mindat with complex formula written as .Khomyakov A. P., Netschelyustov G. N. and Rastsvetaeva R. K. 1990: Alluaivite Na19(Ca,Mn)6(Ti,Nb)3Si26O74Cl.2H2O - A new titanosilicate mineral of eudialyte-like structure. Zapiski Vsesoyuznogo Mineralogicheskogo Obshchestva, 119(3), 117-120, in Jambor J. L. and Puziewicz J. 1991: New mineral names. American Mineralogist, 76, 1728-1735/ref> It is unique among the eudialyte group as the only titanosilicate (other representatives of the group are usually zirconosilicates). The two dual-nature minerals of the group, being both titano- and zirconosilicates, are labyrinthite and dualite. They both contain alluaivite module in their structures.Khomyakov, A.P., Nechelyustov, G.N., and Rastsvetaeva, R.K., 2006. Labyrinthite (Na,K,Sr)35Ca12Fe3Zr6TiSi51O144(O,OH,H2O)9Cl3, a new mineral with a modular eudialyte-like structure from Khibiny Alkaline Massif, Kola ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ilyukhinite
Ilyukhinite is a very rare mineral of the eudialyte group, with formula .Chukanov, N.V., Rastsvetaeva, R.K., Rozenberg, K.A., Aksenov, S.M., Pekov, I.V., Belakovskiy, D.I., and Kristiansen, R., 2015, Ilyukhinite, IMA 2015-065. CNMNC Newsletter No. 28, December 2015, 1860; Mineralogical Magazine 79, 1859–1864 The formula given is simplified and does not show the presence of cyclic silicate groups. Ilyukhinite is the second group representative with species-defining hydronium In chemistry, hydronium (hydroxonium in traditional British English) is the common name for the aqueous cation , the type of oxonium ion produced by protonation of water. It is often viewed as the positive ion present when an Arrhenius acid is d ... ion after aqualite. References Further reading * Johnsen, O., Ferraris, G., Gault, R.A., Grice, D.G., Kampf, A.R., and Pekov, I.V., 2003. The nomenclature of eudialyte-group minerals. The Canadian Mineralogist 41, 785–794 Cyclosilicates Calcium minerals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ikranite
Ikranite is a member of the eudialyte group, named after the Shubinov Institute of Crystallography of the Russian Academy of Sciences. It is a cyclosilicate mineral that shows trigonal symmetry with the space group ''R''3''m'', and is often seen with a pseudo-hexagonal habit. Ikranite appears as translucent and ranges in color from yellow to a brownish yellow. This mineral ranks a 5 on Mohs Scale of Hardness, though it is considered brittle, exhibiting conchoidal fracture when broken. The eudialyte group The eudialyte group currently consists of 27 known minerals (see below), all considered rare, with the exception of eudialyte. The list below also includes one of around six unnamed ("UM") species listed by Mindat.Mindat, http://www.mindat.org This group is growing exponentially, with 17 members having been written about since 2000, and the chemical possibility of several thousand species that have yet to be discovered. Eudialyte group members are typically found as small cryst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golyshevite
Golyshevite is a rare mineral of the eudialyte group,Mindat, Golyshevite, http://www.mindat.org/min-27418.html with the formula Na10Ca3Ca6Zr3Fe2SiNb(Si3O9)2(Si9O27)2CO3(OH)3•H2O. The original formula was extended to show both the presence of cyclic silicate groups and silicon at the M4 site, according to the nomenclature of the eudialyte group.Johnsen, O., Ferraris, G., Gault, R.A., Grice, D.G., Kampf, A.R., and Pekov, I.V., 2003. The nomenclature of eudialyte-group minerals. The Canadian Mineralogist 41, 785-794 The characteristic feature of golyshevite is calcium-rich composition, with calcium at two main sites instead of one site.Chukanov, N.V., Moiseyev, M.M., Rastsvetayeva, R.K., Rozenberg, K.A., and Zadov, A.E., 2005. Golyshevite (Na,Ca)10Ca9(Fe3+,Fe2+)2Zr3NbSi25O72(CO3)(OH)3·H2O, and Mogovidite, Na9(Ca,Na)6Ca6(Fe3+,Fe2+)2Zr3[]Si25O72(CO3)(OH,H2O)4, new eudialyte-group minerals from calcium-rich agpaitic pegmatites of the Kovdor massif, Kola Peninsula. Zapiski Rossiyskogo M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georgbarsanovite
Georgbarsanovite is a very rare mineral of the eudialyte group,Mindat, http://www.mindat.org/min-27506.html formerly known under unaccepted name as barsanovite, with formula .Khomyakov, A.P., Nechelyustov, G.N., Ekimenkova, I.A., and Rastsvetayeva, R.K., 2005. Georgbarsanovite, , a mineral species of the eudialyte group: revalidation of barsanovite and the new name of the mineral. Zapiski Rossiyskogo Mineralogicheskogo Obshchestva 134(6), 47-57 (in Russian, with English abstract) The original formula was extended to show the presence of cyclic silicate groups and the domination of silicon at the M4 site.Johnsen, O., Ferraris, G., Gault, R.A., Grice, D.G., Kampf, A.R., and Pekov, I.V., 2003. The nomenclature of eudialyte-group minerals. The Canadian Mineralogist 41, 785-794 "REE", standing for rare earth elements, is dominated by cerium. Georgbarsanovite is characterized in dominance of manganese at the N4 site. It also differs from most other accepted group representatives in its co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferrokentbrooksite
Ferrokentbrooksite is a moderately rare mineral of the eudialyte group,Mindat, Ferrokentbrooksite, http://www.mindat.org/min-7106.html with formula .Johnsen, O., Grice, J.D., and Gault, R.A., 2003: Ferrokentbrooksite, a new member of the eudialyte group from Mont Saint-Hilaire, Quebec, Canada. The Canadian Mineralogist 41(1), 55-60 The original formula was extended form to show the presence of cyclic silicate groups and presence of silicon at the M4 site, according to the nomenclature of eudialyte group. As suggested by its name, it is the (ferrous) iron analogue of kentbrooksite. When compared to the latter, it is also chlorine-dominant instead of being fluorine-dominant. The original (holotype) material is also relatively enriched in rare earth elements, including cerium and yttrium. Occurrence and association Ferrokentbrooksite was discovered in Mont Saint-Hilaire, Quebec, Canada - a site wealth in rare alkaline minerals. At the site ferrokentbrooksite coexists with aegirine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fengchengite
Fengchengite is a rare mineral of the eudialyte groupMindat, Fengchengite, http://www.mindat.org/min-42378.html with the formula .Shen, G., Xu, J., Yao, P., and Li, G., 2011. Fengchengite, IMA 2007-018a. CNMNC Newsletter No. 11, December 2011, 2892; Mineralogical Magazine 75, 2887-2893 The formula is simplified as it does not show the presence of cyclic silicate groups. When compared to other minerals of the group, fengchengite characterizes in the presence of ferric iron (thus similar to ikranite Ikranite is a member of the eudialyte group, named after the Shubinov Institute of Crystallography of the Russian Academy of Sciences. It is a cyclosilicate mineral that shows trigonal symmetry with the space group ''R''3''m'', and is often seen ..., mogovidite and feklichevite) and essential, site-dominating vacancies. The mineral was discovered in the Saima complex near Fengcheng city in China - hence its name. References Further reading * Johnsen, O., Ferraris, G., Gault, R.A. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feklichevite
Feklichevite is a rare mineral of the eudialyte group with the formula Na11Ca9(Fe3+,Fe2+)2Zr3NbSi(Si3O9)2(Si9O27)2.Pekov, I.V., Ekimenkova, I.A., Chukanov, N.V., Rastsvetaeva, R.K., Kononkova, N.N., Pekova, N.A., and Zadov, A.E., 2001. Feklichevite Na11Ca9(Fe3+,Fe2+)2Zr3Nb i25O73OH,H2O,Cl,O)5, a new mineral of the eudialyte group from Kovdor Massif, Kola peninsula. Zapiski Vserossijskogo Mineralogicheskogo Obshchestva 130(3), 55-65Mindat, Feklichevite, http://www.mindat.org/min-11029.html The original formula was extended to show the presence of cyclic silicate groups and presence of silicon at the M4 site, according to the nomenclature of eudialyte group.Johnsen, O., Ferraris, G., Gault, R.A., Grice, D.G., Kampf, A.R., and Pekov, I.V., 2003. The nomenclature of eudialyte-group minerals. The Canadian Mineralogist 41, 785-794 When compared to other minerals of the group, feklichevite characterizes in the presence of ferric iron (thus similar to ikranite, mogovidite and fengchengite) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eudialyte
Eudialyte, whose name derives from the Greek phrase , , meaning "well decomposable", is a somewhat rare, nine member ring cyclosilicate mineral, which forms in alkaline igneous rocks, such as nepheline syenites. Its name alludes to its ready solubility in acid. Eudialyte was first described in 1819 for an occurrence in nepheline syenite of the Ilimaussaq intrusive complex of southwest Greenland. Uses of eudialyte Eudialyte is used as a minor ore of zirconium. Another use of eudialyte is as a minor gemstone, but this use is limited by its rarity, which is compounded by its poor crystal habit. These factors make eudialyte of primary interest as a collector's mineral. Eudialyte typically has a significant content of U, Pb, Nb, Ta, Zr, Hf, and rare earth elements (REE). Because of this, geoscientists use eudialyte as a geochronometer to date and investigate the genesis of the host rocks. Associated minerals Eudialyte is found associated with other alkalic igneous minerals, in addit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dualite
Dualite is a very rare and complex mineral of the eudialyte group, its complexity being expressed in its formula .Mindat, Dualite, http://www.mindat.org/min-27578.htmlKhomyakov, A.P., Nechelyustov, G.N., and Rastsvetaeva, R.K., 2009: Dualite, Na30(Ca,Na,Ce,Sr)12(Na,Mn,Fe,Ti)6Zr3Ti3MnSi51O144(OH,H2O,Cl)9, a new zircono-titanosilicate with a modular eudialyte-like structure from the Lovozero alkaline Pluton, Kola Peninsula, Russia. Geology of Ore Deposits 50(7), 574-582 The formula is simplified as it does not show the presence of cyclic silicate groups. The name of the mineral comes from its dual nature: zircono- and titanosilicate at once. Dualite has two modules in its structure: alluaivite one and eudialyte one. After alluaivite and labyrinthite it stands for third representative of the eudialyte group with essential titanium. Occurrence and association Dualite was found in peralkaline pegmatoid rock at Mt Alluaiv, Lovozero massif, Kola Peninsula Russia. It associates with aeg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
