... the available specimens it is possible to infer that a blocky albite unit and masses of quartz (quartz cores) formed the main units of the dike. The pegmatite, composed mainly of primary albite (Ab 96 –Ab 100 ), also contains primary chrysoberyl, almandine, schorl, and muscovite as common accessory minerals...

... and the so-called alexandrite effect wherein the perceived color of a mineral changes with different lighting conditions (i.e., daylight vs. incandescent light). In this article we have collected ultraviolet/visible/near-infrared (UV-Vis-NIR) spectra of a gem-quality, synthetic Cr-bearing chrysoberyl crystal...

...Sandra Drev; Matej Komelj; Matjaž Mazaj; Nina Daneu; Aleksander Rečnik Abstract We studied V-shaped twins of chrysoberyl (BeAl 2 O 4 ) from Rio das Pratinhas pegmatites near Arataca in the Bahia state of Brazil. The local structure of the twin boundaries was determined using powder X-ray...

... (beryl, chrysoberyl, bertrandite, euclase, trilithionite, Li-muscovite, petalite, pollucite), rare element-bearing oxide minerals (columbite-tantalite, bismutotantalite, Nb-rutile, cassiterite, hübnerite, qitianlingite), phosphate minerals (triplite, lithiophilite, Mn-rich apatite, xenotime, monazite...

...-REE-U oxide, Y-REE phosphate, Mn-Fe-phosphate, Ti-Zr-silicate, Be-Y-REE-U-silicate and oxide minerals (beryl, chrysoberyl, bertrandite, bavenite, and milarite), garnet (almandine-spessartine), tourmaline (schorl to rare elbaite), bismuthinite, magnetite, and rarely dumortierite and helvite...

... and kyanite as the major phases; the accessory and trace minerals include beryl, chrysoberyl, garnet, fluorapatite, columbite-(Mn) to tantalite-(Mn), pollucite, gahnite, zircon, uraninite and thorite. Holmquistite was found in the exocontact assemblage. Primary textures of magmatic origin were partially...

...P. J. Downes; A. W. R. Bevan Abstract A deposit of chrysoberyl (BeAl 2 O 4 ), including the variety alexandrite, occurs near Dowerin, in the southwestern region of the Archaean Yilgarn Craton, Western Australia. The deposit is situated in the northern part of the Lake Grace Terrain, a crustal...

... for special optical purposes, and as gemstones. Beryl, ideally Al 2 Be 3 Si 6 O 18 , bertrandite, Be 4 Si 2 O 7 (OH) 2 , and phenakite, Be 2 SiO 4 are mined and processed as ores of Be. Beryl and chrysoberyl are used as maser and laser crystals, and bromellite BeO has outstanding properties...

... chrysoberyl, emerald and phenakite. The pegmatite is associated with a two-mica peraluminous Hercynian granite, and intrude dunites of the Schistose domain in the Galician Tras-Os-Montes Zone. The composition of fluid inclusions in emerald and phenakite has been determined using a Raman microprobe...

...Joseph M. Evensen; David London; Richard F. Wendlandt Abstract Beryllium contents of granitic melts at saturation in beryl (+ or - chrysoberyl, phenakite, or quartz) have been determined by forward- and reverse-direction experiments at 650-850 degrees C and 200 MPa using natural beryl...

... of chrysoberyl have been measured from 340 to 800 K. The resulting data have been combined with solution and phase-equilibrium experimental data and simultaneously fit using the program phas20 to provide an internally consistent set of thermodynamic properties for several important beryllium phases...

...Mark D. Barton Abstract The phase relations and thermodynamic properties of behoite (Be(OH) 2 ), bertrandite (Be 4 Si 2 O 7 (OH) 2 ), beryl (Be 3 Al 2 Si 6 O 18 ), bromellite (BeO), chrysoberyl (BeAl 2 O 4 ), euclase (BeAlSiO 4 (OH)), and phenakite (Be 2 SiO 4 ) have been quantitatively evaluated...

...Edward S. Grew Abstract Sunnamite, taaffeite, beryllian sapphirine, niobian rutile, chrysoberyl, and wagnerite occur in sillimanite-rich, medium-grained segregations in two pegmatites of probable late Archean age which cut granulite-facies rocks near McIntyre Island (67°22′S, 49°05′E) in Casey Bay...

...D. M. Burt Abstract Seven commonly associated minerals in the system BeO–Al 2 O 3 –SiO 2 –H 2 O include chrysoberyl, phenakite, euclase, bertrandite, beryl, kaolinite, and quartz. The phase rule implies that not more than six of these minerals can coexist at an invariant point...

...Dale A. Huckaby; Terry L. Wright; Arthur J. Ehlmann Abstract An absorption band near 780 cm -1 in the infrared spectra of behoite [β-Be(OH) 2 ] and of chrysoberyl [Al 2 BeO 4 ] was assigned to the vibration of a beryllium atom moving in a tetrahedral cage of four fixed oxygen atoms. Using...

...E. F. Farrell; R. E. Newnham Abstract The optical absorption spectra of the isomorpbous minerals chrysoberyl, alexandrite, peridot, and sinhalite have been measured in polarized light at 77° K. Electronic transitions between the 6 A 1 ground state of Fe 3+ and a number of quartet states give rise...