The Cs-bearing (∼ 3.5 wt % of Cs 2 O in average) analcime from the Mariinskoe deposit (the Urals Emerald Mines) occurs in well-formed tetragon-trioctahedron colorless or milky-white crystals from 1 to 7 mm in size. Most often the mineral overgrows on albite or phrenite and has the later hydrothermal origin. Single-crystal X-ray diffraction study revealed its cubic symmetry, space group Ia3d, a = 13.714(2) A, V= 2579.0(6) A 3 . Crystal structure was solved to R 1 = 0.037 on the basis of 157 independent reflections with F > 3σ(F). The crystal chemical formula of analcime based on the refined site-scattering factors Na 0.78 [(H 2 O) 0.92 Cs 0.08 ]Al 1.08 Si 1.92 (O 5.78 OH 0.22 ) is in well agreement with the formula calculated on the base of electron-microprobe data: Na 0.79 [(H 2 O) 0.95 Cs 0.05 )Al 0.98 Si 2.02 (O 5.86 OH 0.14 ). Substitution in the extra-framework part corresponds to the scheme Na + + H 2 O = + + Cs + . We revealed the optical anisotropy of cubic analcime which can be explained by the deficiency of water molecules.

Translated title of the contributionANALCIME OF THE MARIINSKOE DEPOSIT (URALS EMERALD MINES, THE MIDDLE URALS): CHEMICAL COMPOSITION AND CRYSTAL STRUCTURE
Original languageRussian
Pages (from-to)111-120
Number of pages10
JournalZapiski Rossiiskogo Mineralogicheskogo Obshchestva
Volume146
Issue number4
StatePublished - 1 Jan 2017

    Research areas

  • Analcime, Cesium, Crystal structure, Mariinskoe deposit, Urals emerald mines

    Scopus subject areas

  • Geochemistry and Petrology
  • Geology
  • Economic Geology
  • Materials Chemistry

ID: 42535199