... to that of chiappinoite-(Y), although several other silicate minerals have structures containing thick tetrahedral layers, e.g. amstallite ( Quint, 1987 ), kvanefjeldite ( Johnsen et al. , 1983 ) and lemoynite ( Le Page & Perrault, 1976 ). The paper benefited from comments by two anonymous reviewers...

... structures containing thick layers of tetrahedra, e . g ., amstallite ( Quint 1987 ), kvanefjeldite ( Johnsen et al. 1983 ), lemoynite ( Le Page & Perrault 1976 ), and chiappinoite-(Y) ( Kampf & Housley 2014 ). Associate Editor James Evans, reviewer Frank Hawthorne, and an anonymous...

...Fig. 25. Insertion of pairs of 2-connected vertices into the 6 3 net; ( a ) view and cross-section of the inserted 6 3 net; ( b ) the net of the sheet of tetrahedra in amstallite ; ( c ) the sheet of tetrahedra in amstallite ; and ( d ) horizontal view of the sheet of tetrahedra...

..., vivianite, xenotime-(Y), monazite-(Ce), allanite-(Ce), amstallite, siderite, calcite, and laumontite ( Ertl 1995 ). In this study we focus on the crystal structure of one of the most V-rich muscovites reported to date, with an average of 11.35 wt.% V 2 O 3 , and on the optical absorption spectra...

... of the parent net become 4-connected; ( c ) the net in amstallite ; (d) the sheet of tetrahedra in amstallite . Yellow vertices and tetrahedra are 2-connected. ...

... to distinguish these minerals, stoichiometric formulae are obviously needed. It should be noted that, in general, the structure type should be considered for minerals that occur in several polymorphic modifications, which should be distinguished from the minerals that have no polymorphs ( e.g. , amstallite...

..., possibly amstallite (CaAl(Si,Al) 4 O 8 (OH) 4 ·((H 2 O),Cl). This mineral was first recorded from a graphite quarry in Amstall, Austria, and results from hydrothermal alteration of metamorphosed carbonaceous rocks ( Quint, 1987 ). Figure 18: Mineralogy of oil-impregnated limestone of the Al-Kharazeh...

... of esquireite is unique, although several other silicate minerals contain thick layers of tetrahedra in their structures: amstallite, kvanefjeldite, lemoynite, and chiappinoite-(Y). The name esquireite is for one of the type localities, the Esquire #1 claim. Five cotype specimens have been deposited...

... 2.50 Gyrolite S 3 V 2 Eudidymite R 3 V 2 2.50 Antigorite S 3 V 2 Caysichite-(Y) R 3 V 2 2.50 Prehnite S 2 V 2 4 V 2 Tuhualite R 3 V 2 2.50 Amstallite S 2 V 4 4 V 4 Syn. Cs 4 Y 2 [Si 8 O 20 ]F 4 R 3 V 8 2.50 Apophyllite S 3 V 8...