...Paula C. PIILONEN; Andrew M. McDONALD; André E. LALONDE Abstract The crystal structures of two kupletskite [K 2 NaMn 7 Ti 2 Si 8 O 26 (OH) 4 F] polytypes, (1) triclinic, space group P 1̄, and (2) monoclinic, space group C 2/ c , from nepheline syenite pegmatites of the Lovozero massif, Russia...

...P. Bayliss Abstract Cesium kupletskite has been renamed kupletskite-(Cs) with the approval of the IMA Commission on New Minerals, Nomenclature and Classification, because the name of a mineral species should be a single word and the International Union of Pure and Applied Chemistry spelling...

...Elena Sokolova; Fernando CÁmara; Frank C. Hawthorne; Marco E. Ciriotti Abstract Zircophyllite is redefined as an astrophyllite-group mineral, ideally K 2 NaFe 2+ 7 Zr 2 (Si 4 O 12 ) 2 O 2 (OH) 4 F (Fe 2+ -dominant at C 7 ) (IMA 17-D). Zircophyllite was previously considered to be a kupletskite...

... of kupletskite-(Cs) are incorrect. We report here the correct values: In Table 6, in the < A –ϕ>** (Å) column, < A (2)–ϕ> = 2.57 for Sn-rich astrophyllite. In Table 7, in the < A – ϕ> obs ** (Å) column, < A (2)–ϕ> obs = 2.57 for Sn-rich astrophyllite. In the A – A (Å...

...Fernando Cámara; Elena Sokolova; Yassir Abdu; Frank C. Hawthorne Abstract The crystal structures of niobophyllite, K 2 Na Fe 2+ 7 (NbTi) (Si 4 O 12 ) 2 O 2 (OH) 4 O, kupletskite-(Cs), Cs 2 Na Mn 7 Ti 2 (Si 4 O 12 ) 2 O 2 (OH) 4 F, and Sn-rich astrophyllite, K 2 Na Fe 2+ 7 Ti 2 (Si 4 O 12 ) 2 O 2...

...P. C. Piilonen; I. V. Pekov; M. Back; T. Steede; R. A. Gault Abstract The chemistry and crystal structure of a unique Zn-rich kupletskite: (K 1. 55 Na 0 .2 1 Rb 0. 09 Sr 0 . 01 ) ∑1 .8 6 (Na 0 .8 2 Ca 0 . 18 ) ∑1 .0 0 (Mn 4. 7 2 Zn 1 .6 6 Na 0. 41 Mg 0. 12 Fe 0. 09 2+ ) ∑7 . 00 (Ti 1.85 Nb 0.11 Hf...

... diversity in species and range in chemical composition. Kupletskite-subgroup samples are enriched in Na, Mn, Fe 3+ , Zn, Zr and Nb, whereas astrophyllite-subgroup samples are enriched in K, Ca, Fe 2+ , Ti, Zr and Al. Enrichment of kupletskite-subgroup samples in Fe 3+ , Mn and Nb suggests crystallization...

.... The HOH layer is characterized by a planar cell with a ~5.4, b ~11.9 Å and a ^ b ~103°. The ideal composition of the O sheet is Fe 7 2 + (astrophyllite) or Mn 7 2 + (kupletskite). All structures consist of an HOH layer and an I (intermediate) block that consists of atoms between two HOH layers...

..., niobophyllite, zircophyllite, tarbagataite, nalivkinite and bulgakite. In the kupletskite group (HOH blocks connect via D– –D bridges, Mn 2+ is dominant at C 7 ), there are three minerals: kupletskite, niobokupletskite and kupletskite-(Cs). In the devitoite group (HOH blocks do not connect via D– –D bridges...

...Elena Sokolova; Maxwell C. Day; Frank C. Hawthorne; Anatoly V. Kasatkin; Robert T. Downs; László Horváth; Elsa Pfenninger-Horváth Abstract Laverovite (IMA 2017-009b), ideally K 2 NaMn 7 Zr 2 (Si 4 O 12 ) 2 O 2 (OH) 4 F, is a kupletskite-group (astrophyllite-supergroup) mineral from Mont Saint...

..., Zn-bearing kupletskite, aegirine, perraultite, fluorite, catapleiite, serandite, REE -rich eudyalite, fluorapatite, fluorbritholite-(Ce), a pyrochlore-group mineral, cryolite, thorite, thorianite and a mineral of the cancrinite group. Fine-grained phonolite from the Oktyabrsky massif represents...

... orange in color, with a white streak and vitreous luster. Bladed crystals are prismatic, having forms {111̅} and {101̅}; they are elongate on [101], up to 10 mm in length. Associated minerals include aegirine, albite, analcime, ancylite-(Ce), calcite, catapleiite, gonnardite, hydrotalcite, kupletskite...

... minerals are anatase, arsenopyrite, fluorapatite, fluorite, halloysite, heulandite-Ca, heulandite-Sr, kupletskite, lamprophyllite, leucophanite, magnesio-arfvedsonite, mangan-neptunite, microcline, monazite-(La), polylithionite, quartz, opal, rhabdophane-(Ce) and titanite. The mineral is transparent...

..., reedmergnerite, cesium-kupletskite, hyalotekite, albite, dusmatovite, pyrochlore, tadzhikite, tienshanite, sogdianite, stillwellite-(Ce), leucosphenite, leucophanite, willemite, danburite, zektzerite, berezanskite, baotite, cappelenite-(Y) and an unknown Y–Ca silicate. Pekovite occurs in a rock consisting mainly...

...] single [Si 4 O 12 ] 8− chains cross-linked by corner-sharing D ϕ 6 octahedra in triclinic species and kupletskite- Ma 2 b 2 c , and D O 5 polyhedra in magnesium astrophyllite. Distortion of the D ϕ 6 octahedron is minimized by (Nb,Zr) ⇔ Ti substitution, resulting in displacement of the cation toward...

..., galena, genthelvite, gmelinite, gonnardite, horváthite-(Y), kupletskite, leifite, microcline, molybdenite, narsarsukite, natrolite, nenadkevichite, petersenite-(Ce), polylithionite, pyrochlore, quartz, rhodochrosite, rutile, sabinaite, sérandite, siderite, sphalerite, thomasclarkite-(Y), zircon...