... and shakhdaraite-(Y)]; columbite type [columbite-group minerals; a = 3 a 0, b = b 0 and c = c 0 ; Pbcn ; the members are columbite-(Fe), columbite-(Mn), columbite-(Mg), tantalite-(Fe), tantalite-(Mn), tantalite-(Mg), fersmite, euxenite-(Y), tanteuxenite-(Y) and uranopolycrase]; and wodginite type [wodginite-group...

..., dumortierite, and tourmaline-supergroup minerals, (b) rare-element- and rare-earth-element-bearing minerals such as columbite-(Fe), uranopolycrase, fergusonite-(Y), uraninite, xenotime-(Y), and monazite-(Ce), (c) Ca-, F-, and K-dominant amphiboles, (d) phosphates (fluorapatite, isokite, wagnerite), (e...

...Fig. 8 SEM micrograph of the titanite crystals in the albitized zones being replaced by a fine-grained association of niobian rutile (with ilmenite exsolution-induced lamellae), thorutite, polycrase-(Y), and uranopolycrase. The gray host mineral is allanite-(Ce). ...

... in the pockets. Euxenite-(Y), polycrase-(Y), U–Bi-rich polycrase-(Y), and ferrocolumbite occur in the primitive pockets in the central part (core zone), whereas U–Bi-rich polycrase-(Y), uranopolycrase, manganocolumbite, manganotantalite, “wolframo-ixiolite”, titanowodginite and microlite are found in the evolved...

... = euxenite-(Y), Uplc = uranopolycrase, Wdg = wodginite, Fwdg = ferrowodginite, Twdg = titanowodginite, Ftwdg = ferrotitanowodginite, Ttwdg = tantalowodginite and Ahl = Achalaite. ...

... a negative correlation, between either U 4+ and Ca 2+ , or these elements and Y 3+ or REE 3+ . According to Černý & Ercit (1989) , U 4+ in the AB 2 O 6 structure can be explained by a solid solution between euxenite-(Y) and a uranopolycrase endmember (UTi 2 O 6 ), which involves vector (5...

...), Y(Ta,Nb,Ti) 2 (O,OH) 6 ; polycrase-(Y), Y(Ti,Nb) 2 (O,OH) 6 ; uranopolycrase, (U,Y)(Ti,Nb,Ta) 2 (O,OH) 6 ; and fersmite, (Ca,Ce,Na)(Nb,Ta,Ti) 2 (O,OH,F) 6 . Yttrocrasite-(Y), (Y,Th,Ca,U)(Ti,Fe) 2 (O,OH) 6 is of questionable status. Except for fersmite, the EGM are typically metamict owing...

.... English translation in Dokl. Acad. Sci. USSR Earth Sci. Sect ., 153 , 129 – 131 . Aurisicchio , C. , Orlandi , P. , Pasero , M. , Perchiazzi , N. ( 1993 ): Uranopolycrase, the uranium-dominant analogue of polycrase-(Y), a new mineral from Elba Island, Italy, and its crystal...

...), thorite, zircon, monazite-(Ce), cassiterite, magnetite, fluorapatite, fluorite, beryl, titanite, and rutile; rare accessory minerals are scheelite and hambergite ( Dzhurayev et al . 1998 ), Sc-bearing tusionite ( Mirakov et al . 2018b ), high-B crystalline gadolinite, uranopolycrase, allanite-(Ce...

... . 35 , 386 – 400 . Aurisicchio , C. , Orlandi , P. , Pasero , M. & Perchiazzi , N. ( 1993 ): Uranopolycrase, the uranium-dominant analogue of polycrase-(Y), a new mineral from Elba Island, Italy, and its crystal structure . Eur. J. Mineral . 5 , 1161 – 1165...

...,Nb) 2 O 6 . Members of the euxenite group include euxenite-(Y), Y(Nb,Ti) 2 O 6 , tanteuxenite-(Y), Y(Ta,Ti,Nb) 2 O 6 , polycrase-(Y), Y(Ti,Nb) 2 O 6 , and uranopolycrase, UTi 2 O 6 . The aeschynite structure shows a preference for larger A cations than the euxenite structure; hence aeschynite-group...

... rutile, thorutite, polycrase-(Y), uranopolycrase and aeschynite-(Y). In 160b/62, aeschynite-(Y) and aeschynite-(Ce) occur in the unaltered and altered chevkinite zones and in the allanite zone, sometimes but not invariably associated with, and derived from, titanite or rutile. Whilst it is difficult...

.... Polycrase-(Y) also is found in those cavities, along with columbite-(Fe), tourmaline and beryl. The later-formed cavities, located at the termination of dikes, contain columbite-(Mn) with a rim of tantalite-(Mn) ( Fig. 7 ), together with manganoan elbaite, pink beryl, petalite, microlite, uranopolycrase...