 | | Journal (article/letter/editorial) | | ABsrRAcr The Climax pegmatite of the Micanite district in Colorado contains unusually large masses of...discussed. IurnooucttoN The Micanite pegmatite district iies acrossthe Park-Fremont County line in south-centralColorado...of massive white quartz or ol coarse microcline crystals together with massive quartz pods. Concentrations...grinding quality muscovite were obtained. Within the district ten major quarriesand prospectsare recorded(Fig...HEINRICH The chief minerals of the pegmatites arel. quartz, pink microcline in crystals as much as 10 feet |  | | Journal (article/letter/editorial) | | Shibata (1936, p. 209 and 217) had two mixtures of quartz and iron rich cordierite analyzed there was no... ANALYSES AND PHYSICAL CONSTANTS OF CORDIDRITES quartz and the density and chemical composition had to...calculated from planimetric estimationsof the volume ol quartz in the cordieritequartz mixture. Even now, over...all, in ordinary metamorphic rocks, pegmatitesand quartz veins belong to the Iow subdistortional class,pseudohexagonaland...Pehrman, 1932, p. 5. 4. W. of Karungalpatti, Salem district, Madras, India Corundum-sillimanite-anthophyllite-bytownite |  | | 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 (volume) | | Forsterite, crystalline limestone, Mogok Mining District, Burma (Adams and Graham, 1926). Olivine, with...exist, however, in equilibrium in the assemblage quartz, minnesotaite, Fe3Si40io(OH)2 (a ferrous iron analogue...high and there is a water deficiency, and with quartz and magnetite when no water is present in the sys¬...decomposes to fayalite, quartz and water. Above 480°C. the assemblage fayalite, quartz and water, with or...usually together with goethite, also commonly with quartz and calcite, and more rarely with talc and mica |  | | Report (issue) | | Blue Ridge province _____________ _ Spruce Pine district ____________ Madison County and Haywood County...County _____________________ _ Zirconia district ___________ ----Macon, Jackson, and Clay Counties __ ----...Toluca Quartz Monzonite and microcline-oligoclase-quartz pegmatite, and from unweathered vein quartz exposed...rare-earth composition of monazite from the Cherryville Quartz Monzonite exposed in Cleveland County, N.C----...Africa. Thorium-rich monazite is concentrated in quartz-apatite-monazite veins formed by metamorphic differentiation |  | | Book (edition) | | are clear compar- to scratch glass: These are quartz There are also black grains which, because they... like the greater part of the sand grains, are quartz There are white, yellow, or pale flesh-red . grains...grains, also hard, but not as hard as quartz, smooth surfaces; these ar t feldspar Then which there...Another rock, quartzite, is composed of only quartz Because they . are made up of a single mineral...expressed by a chemical formula. Some for example, quartz: silicon dioxide (Si0 2 ) erals that its composition |  | | Book | | nlineral nan,es with structural terms (for exan1ple, quartz-mica schist, plagioclase-pyroxene granofels) is...classification plots based on SiO 2 vs. Na2 O + K 2 O, or quartz, feldspar, feldspathoid ratios , as used by igneous...using a series of compound hyphenated nan1es (e.g. quartz-1nica schist. lawson ite-glaucophane schist) in...or protolith characteristics (e.g. garnet-n1ica -quartz schist, garnetbiotite aniph;bo/;te, gt,rnet-pyroxene...a1nph ibole and plagioclase); quartzite (in which quartz is by far the n1ajor constituent); marble (in which |
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