| | Journal (article/letter/editorial) | CORDIERITE IN PEGMATITE NEAR MICANITE, COLORADO E. Wtu. Herwucn, UniversityoJ Michigan,Ann Arbor, Mi...pegmatite of the Micanite district in Colorado contains unusually large masses of cordierite, which is altered...pegmatitic and vein cordierite are summarized, and the paragenesis of pegmatitic cordierite is discussed. ... IurnooucttoN The Micanite pegmatite district iies acrossthe Park-Fremont County line in south-centralColorado...1949, at which times some fresh and much altered cordierite was obtained. This collection was supplemented | | | Journal (article/letter/editorial) | correlate the composition and optical properties of cordierite is given, followed by a compilation, including...relationship between the chemical composition of cordierite and its optical properties and density has been...Thus Brammall & Rao (1936, p. 257) showed that cordierite from the Dartmoor Granite varied in 2Va fuorr-56o-72owhile...fuorr-56o-72owhile Tsuboi (1936' p. 337) found that the cordierite in a single rock had a 2Y variation from positive...quartz and iron rich cordierite analyzed there was no information about cordierite richer than 50/6 of | | | Book (volume) | Gehlenite, Melibte, Akermanite ..... 236 BERYL.256 CORDIERITE.268 TOURMALINE.300 AXINITE.320 INDEX.329 NOTES...Forsterite, crystalline limestone, Mogok Mining District, Burma (Adams and Graham, 1926). Olivine, with...* Includes Ni 0-005. Olivine 11 rium with cordierite and spinel can co-exist at water vapour pressures...Si02 + 24H20 clinochlore forsterite spinel cordierite Forsterite has also been crystallized from gels...ternary eutectic at 1083°C. with tridymite and iron-cordierite, and has a second ternary eutectic at 1148°C | | | Journal (issue) | courtesy of Rio Tinto; (4) an 11.16 ct sapphire from Madagascar, GIA Collection no. 31618; (5) a 1.01 ct yellow...competitive rough diamond market. Political problems in Madagascar and a ban on gem exports from Myanmar disrupted...were combined under the jurisdiction of the U.S. District Court of New Jersey 168 PRODUCTION AND MARKETS...for gemstones. New Deposits and New Operations. Madagascar. Much of the global gem business for well over...in the middle of the decade was dominated by Madagascar. This was due in part to the Malagasy PRODUCTION | | | Book (edition) | a shale, the homfels will contain microsopic cordierite, andalusite, biotite, feldspar, and quartz. If...gravels that are called fossil placers. This district, the this case the some places passer. is...time that platinum in 1822 from placers in the district The placer deposits smaller scale by mining...gneisses Adirondack region, particularly at of Madagascar or Ticonderoga in the in the quartz schists...century, native copper from the Lake Superior district was the most important in the United States. Then | | | Book | hornblende (with high Ti-contents). In some granuliLes cordierite ,nay also be present. 2. ln some types of granuljtes...absence of pri1nary n1uscovite are critical, and cordierite n1ay also be present. The 1nineral composition...con1posed of garnet, feldspar and quartz. Biotite and cordierite 111ay be present, as well as kya ni te and sillin1anite...mineral assemblage (sanidine, corundun1, spine!, cordierite ± hypersthene ± glass), overprinted on both regional...n1ineralogical criteria (e.g. mafic. ultran1afic, cordierite-sillimanite-spinel hornfels. diopsidewollastonite-garnet | | | Report (issue) | Blue Ridge province _____________ _ Spruce Pine district ____________ Madison County and Haywood County...County _____________________ _ Zirconia district ___________ ----Macon, Jackson, and Clay Counties __ ----...origin. Quartzite and conglomerate in the Mkushi district of the Central Province of the Federation of Rhodesia...composition intrusive into quartzite in the Diamantina district of Brazil (Derby, 1899, p. 348; 1900a, p. 209-213;...Except for the greenish schist in the Diamantina district, metamorphosed equivalents of mafic igneous rocks |
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