 | | Journal (article/letter/editorial) | | felsic dikes inferred from the composition of gahnite in two new occurrences, Pala Chief and Elizabeth...Abstract We report the occurrence and composition of gahnite ([Zn,Fe,Mg,Mn]Al2O4) in aplites of the Pala Chief...Accessory gahnite occurs as extremely fine-grained (50–250 μm) green to bluish-green crystals. Gahnite compositions...Ghn83.5–90.9Hc8.7–15Spl0–1.4. Zinc contents in gahnite are high (36.7–39.5 wt.% ZnO for Pala Chief, 37...% FeO). Gahnite is chemically zoned and characterized by higher Zn (< 2 wt.% ZnO) and lower Fe, Mg, and |  | | Journal (article/letter/editorial) | | DOI: 10.3749/canmin.1400100 THE COMPOSITION OF GAHNITE IN GRANITIC PEGMATITES FROM THE PAMPEAN PEGMATITE...San Martín, 5500, Mendoza, Argentina ABSTRACT Gahnite from LCT granitic pegmatites of the Comechingones...proportions of endmembers (gahnite, hercynite, spinel, and galaxite) the composition of gahnite in these pegmatites...pegmatites. Gahnite from the Nancy pegmatite has higher Mg and Mn contents than gahnite from the pegmatites...variation within gahnite crystals is characterized by higher Zn (∼2.8 wt.% ZnO) and lower Fe (∼2.6 wt.% |  | Faulstich, Fabiano Richard Leite, Ávila, Ciro Alexandre, Neumann, Reiner, Silveira, Viktor S.L., Callegario, Levi S. (2016) Gahnite From the São João Del Rei Pegmatitic Province, Minas Gerais, Brazil: Chemical Composition and Genetic Implications. The Canadian Mineralogist, 54 (6) 1385-1402 doi:10.3749/canmin.1500091 | Journal (article/letter/editorial) | | 1385-1402 (2016) DOI: 10.3749/canmin.1500091 GAHNITE FROM THE SÃO JOÃO DEL REI PEGMATITIC PROVINCE...plutonism in the Mineiro Belt. A selected group of gahnite crystals from several pegmatite bodies hosted in...exclusively on the gahnite–hercynite axis, and fall into the granitic pegmatite field in the gahnite–spinel–hercynite...gahnite–spinel–hercynite ternary diagram. The composition of gahnite varies depending on the country rock the pegmatite...emplacement of these pegmatitic bodies. Keywords: gahnite, São João del Rei Pegmatitic Province, pegmatite |  | D’Ippolito, V., Andreozzi, G. B., Bosi, F., Hålenius, U., Mantovani, L., Bersani, D., Fregola, R. A. (2013) Crystallographic and spectroscopic characterization of a natural Zn-rich spinel approaching the endmember gahnite (ZnAl2O4) composition. Mineralogical Magazine, 77 (7) 2941-2953 doi:10.1180/minmag.2013.077.7.05 | Journal (article/letter/editorial) | | natural Zn-rich spinel approaching the endmember gahnite (ZnAl2O4) composition V. D’IPPOLITO1,*, G. B. ANDREOZZI1...The composition of the crystal approaches the gahnite endmember (ZnAl2O4), ~94 mol.%, with the remainder...concentration of Fe2+ and Fe3+. K EY WORDS : blue spinel, gahnite, cation ordering, electron microprobe, crystal-structure...optical absorption spectroscopy. Introduction GAHNITE, ideally ZnAl2O4, is a less common member of the...rocks (Heimann et al., 2005). Transparent natural gahnite can be used as a gemstone because of its attractive |
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Siedlimowice granite quarry, Siedlimowice, Gmina Żarów, Świdnica County, Lower Silesian Voivodeship, Poland