...Brent E. Owens; Daniel T. Kremser Abstract We report here an occurrence of cuspidine as part of a complex symplectitic intergrowth formed from the breakdown of åkermanite ( X Mg = 0.97, Na-mel 12 Gh 3 ) in a calc-silicate xenolith in the Kiglapait Intrusion, Labrador, Canada. The symplectite...

...Stefano Merlino; Marcello Mellini § E-mail address : merlino@dst.unipi.it 23 01 2009 © 2009 Mineralogical Association of Canada 2009 In their paper entitled “Marianoite, a new member of the cuspidine group from the Prairie Lake silicocarbonatite, Ontario...

... variations in the M 1 and M 2 polyhedra do Mellini & Merlino (1979 , p. 119–121) actually refer to other cuspidine-group minerals ( Merlino & Mellini 2009 , p. 1277). Hence, it seems entirely appropriate that Chakhmouradian et al. (2008) used the same example ( i.e. , NaNbO 3 ) to illustrate...

... in a groundmass of cuspidine, sodalite, ferroan manganoan monticellite, K-Fe sulphide and manganoan titanian magnetite and gregoryite. The xenocrysts were not in equilibrium with the melt which formed their current host, as clinopyroxenes and Ti-andradite are mantled by cuspidine, and nepheline by sodalite...

...Anton R. Chakhmouradian; Roger H. Mitchell; Peter C. Burns; Yulia Mikhailova; Ekaterina P. Reguir Abstract Marianoite, a new member of the cuspidine group of minerals, occurs in phlogopite–calcite silicocarbonatite in the western part of the Mesoproterozoic Prairie Lake intrusive complex...

... in gregoryite and fractures in nyerereite-gregoryite intergrowths. Silicates include members of the sodian cuspidine–niobian cuspidine–niocalite solid-solution series and manganoan monticellite. Oxides are represented by members of the magnesioferrite–jacobsite–magnetite solid-solution series. Sulphides...

...Ian S. Buick; Roger Gibson; Thomas Wallmach; Jorg Metz Abstract The rare calc-silicate minerals cuspidine, foshagite and hillebrandite occur as late phases in calcsilicate xenoliths from the Rustenburg Layered Suite of the Bushveld Complex. These minerals occur in narrow veins or as replacements...

... 1 / n , a = 10.8730(21) Å, b = 10.5516(25) Å, c = 7.4287(13) Å, and β = 109.74(2)° and twinned by pseudo-merohedry with m (100) as the plane of twinning which was accounted for in the refinement calculations. The crystal belongs to the structure family of the mineral cuspidine and represents...

...A. Wilson; J. K. Leary Abstract Cuspidine(3CaO·CaF 2 ·2SiO 2 )is a rare natural mineral which was first describedby Scacchi. 1 Since that time the mineral has been synthesized by solid state reaction, 2 from melts 3 and hydrothermally. 4 It has also been observed as a constituent of electric...

...A. Van Valkenburg; G. F. Rynders Abstract Cuspidine (3CaO · 2SiO 2 · CaF 2 ) can be synthesized hydrothermally, from crystallizing melts, and by solid state reactions. Efforts to substitute hydroxyl for fluoride ions in the cuspidine structure were not successful, and this suggested that custerite...