 | 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) | | Biotite and andalusite porphyroblasts are also major constituents in MST1002, but the andalusite is replaced...MST1002, Table 5) most typically form a fringe on andalusite or sillimanite bundles replacing it; there also...replacement of werdingite, generally in the vicinity of andalusite or sillimanite, which it could also be replacing;...“boron-mullite” has replaced werdingite adjacent to andalusite. Werdingite shows indistinct zoning. Sample MST1002...composition. Sample MST1002. Abbreviations: A = andalusite, BM = “boron-mullite”, C = cordierite, H = hercynite |  | | Journal (article/letter/editorial) | | conditions consistent with the presence of secondary andalusite. Keywords: schorl, dravite, foitite, dumortierite...pegmatites are cordierite, biotite, sillimanite, andalusite and rutile (Grew et al. 2008a). The borosilicates...borosilicates as well as the D4 pegmatite 121502, whereas andalusite was found in only three D2–D3 pegmatites with...In two of these, microstructures suggest that andalusite is secondary, i.e., it overgrows boralsilite...Photomicrograph (planepolarized light) showing andalusite (And) that has partially replaced grandidierite |  | | Journal (article/letter/editorial) | | members in this family, mullite, sillimanite, and andalusite crystallize in orthorhombic subgroups of the...index 4 for sillimanite and andalusite. Therefore, sillimanite and andalusite can be formally described...with the corresponding chains in sillimanite, andalusite, mullite, and Al18 B4 O33 have been pointed out...mineral from Cap Andrahomana, southwest of Fort Dauphin (Tolanaro) in southern Madagascar. Since then...orthorhombic symmetry. It is closely related to andalusite, Al2 SiO5 , and can be schematically derived |  | 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) | | whereas ominelite-grandidierite, plagioclase, andalusite, and tourmaline are much subordinate. The most...B-free minerals (in these samples, sillimanite and andalusite) through the use of a Faraday Cup. Eighty seconds...301 for Mn2 O3 gave better compatibilities for andalusite and kanonaite than k = 0.176 for Al2 O3 and k...constituents SiO2 , Al2 O3 , Mn2 O3 and Fe2 O3 in andalusite and kanonaite. Synthetic analogues “Boron-mullites”...three series by the names of the Mg end-members. Andalusite and plagioclase is present in a few sections |  | | 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 |
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