 | Grew, E. S., Graetsch, H. A., Poter, B., Yates, M. G., Buick, I., Bernhardt, H.-J., Schreyer, W., Werding, G., Carson, C. J., Clarke, G. L. (2008) Boralsilite, Al16B6Si2O37, and "boron-mullite:" Compositional variations and associated phases in experiment and nature. American Mineralogist, 93 (2) 283-299 doi:10.2138/am.2008.2571 | Journal (article/letter/editorial) | | K-feldspar (Buick et al. 2006 and in preparation). Biotite and andalusite porphyroblasts are also major constituents...contact with cordierite, and locally with hercynite, biotite, and K-feldspar (as an inclusion). The “boronmullite”...metapelites commonly contain the assemblage quartz + biotite + cordierite + K-feldspar ± orthopyroxene ± garnet...and high-Al metapelites, quartz + K-feldspar + biotite + cordierite + sillimanite + hercynite (e.g., Greenfield...which is found in five of the nine pegmatites. Biotite, cordierite, and wagnerite are also present in |  | | Journal (article/letter/editorial) | | unpubl. data). The most abundant B-rich units are biotite–plagioclase gneisses, with local enrichments of...occurring sparingly in the pegmatites are cordierite, biotite, sillimanite, andalusite and rutile (Grew et al...metasomatizing hydrothermal fluids and breakdown of biotite in the presence of melt. There is no evidence,...boron to produce tourmaline from breakdown of biotite. London et al. (2002) concluded that the rapid...temperature. Thomson (2006) suggested, by analogy with biotite, that Ti incorporation is favored by high temperature |  | Buick, Ian S., Grew, Edward S., Armbruster, Thomas, Medenbach, Olaf, Yates, Martin G., Bebout, Gray E., Clarke, Geoffrey L. (2008) Boromullite, Al9BSi2O19, a new mineral from granulite-facies metapelites, Mount Stafford, central Australia: a natural analogue of a synthetic "boron-mullite". European Journal of Mineralogy, 20 (5) 935-950 doi:10.1127/0935-1221/2008/0020-1809 | Journal (article/letter/editorial) | | μm). Sekaninaite-cordierite, potassium feldspar, biotite, werdingite and its Fe-dominant analogue, hercynite...K-feldspar are abundant in all the sections, whereas biotite, hercynite and ilmenite are subordinate and quartz...by the following reaction involving anatexis: Biotite + andalusite/sillimanite + tourmaline ± quartz...with hercynite, and what appears to be secondary biotite. Pressure-temperature conditions for the borosilicate...dumortierite to higher temperature as it does biotite (Patiño Douce, 1993) or to lower bulk SiO2 contents |  | | Report (issue) | | The Natural History Museum of Milan and its Madagascar Collection The Museo Civico di Storia Naturale... the museum began paleontologic fieldwork in Madagascar (upper Permian fauna and Jurassic and Cretaceous...fieldwork in Madagascar in 1996 in collaboration with other institu tions in Madagascar, Italy, and the...Pezzotta has spent a total of twenty nine months in Madagascar making geological-mineralogical surveys. In collaboration...both classic and new minerals and gemstones from Madagascar opened at the Natural History Museum in Milan |  | | Journal (issue) | | Albite, 11.2 cm, from the La Marina mine, Muzo District, Boyaca Department, Colombia. See the article...Hodrusa-Hamre (in the Banska Stiavnica mining district) is also the type locality for hodrusite. V INTRODUCTION...historical events before 1920, we will use the older district name of Schemnitz in accordance with the literature...time, whereas for events after 1920 the modem district name of Banska Stiavnica will be used, bearing...to the same district. A list of the names of other sites in the Hanska Stiavnica district is given in |
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