Английская Википедия:Abenakiite-(Ce)

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Шаблон:Short description Шаблон:Infobox mineral Abenakiite-(Ce) is a mineral of sodium, cerium, neodymium, lanthanum, praseodymium, thorium, samarium, oxygen, sulfur, carbon, phosphorus, and silicon with a chemical formula Na26Ce6(SiO3)6(PO4)6(CO3)6(S4+O2)O. The silicate groups may be given as the cyclic Si6O18 grouping. The mineral is named after the Abenaki, an Algonquian Indian tribe of New England. Its Mohs scale rating is 4 to 5.[1]

Occurrence and association

Abenakiite-(Ce) was discovered in a sodalite syenite xenolith at Mont Saint-Hilaire, Québec, Canada, together with aegirine, eudialyte, manganoneptunite, polylithionite, serandite, and steenstrupine-(Ce).[1][2]

Notes on chemistry and relation to other species

Combination of elements in abenakiite-(Ce) is unique. Somewhat chemically similar mineral is steenstrupine-(Ce).[2][3] The hyper-sodium abenakiite-(Ce) is also unique in supposed presence of sulfur dioxide ligand. With a single grain (originally) found, abenakiite-(Ce) is extremely rare.[1]

Crystal structure

In the crystal structure, described as a hexagonal net, of abenakiite-(Ce) there are:[1]

  • chains of NaO7 polyhedra, connected with PO4 groups
  • columns with six-membered rings of NaO7, and NaO7-REEO6, and SiO4 polyhedra (REE - rare earth elements)
  • CO3 groups, NaO6 octahedra, and disordered SO2 ligands within the columns

See also

References

Шаблон:Reflist

External links


Шаблон:Silicate-mineral-stub

  1. 1,0 1,1 1,2 1,3 McDonald, A.M., Chao, G.Y., and Grice, J.D., 1994. Abenakiite-(Ce), a new silicophosphate carbonate mineral from Mont Saint-Hilaire, Quebec: Description and structure determination. The Canadian Mineralogist 32, 843-854
  2. 2,0 2,1 Mindat, Abenakiite-(Ce), Mindat.org
  3. Шаблон:Cite web