...Paul Alexandre ABSTRACT The emerald deposits in Rajasthan, northwest India, are situated in a narrow NE–SW belt in the Aravalli Mountains. The studied deposits were formed by the metasomatic reaction between muscovite (± garnet ± tourmaline) pegmatites and lenticular bodies of altered ultramafic...

...Gerhard Franz; Oleksii Vyshnevskyi; Michail Taran; Vladimir Khomenko; Michael Wiedenbeck; Ferry Schiperski; Jörg Nissen Abstract We investigated emerald, the bright-green gem variety of beryl, from a new locality at Kruta Balka, Ukraine, and compare its chemical characteristics with those...

...Xin Qiao; Zhengyu Zhou; Dietmar Theodor Schwarz; Lijian Qi; Jiaxin Gao; Peizhen Nong; Meng Lai; Kaipeng Guo; Yingbo Li Abstract Natural emeralds from 11 mining areas were studied using an infrared spectrometer. The results showed different spectroscopic characteristics for emerald from different...

... single individuals. There are only a few examples of fast growth leading to gem-quality edifices: examples include “gota de aceite” Colombian emerald or the dendritic “pseudo cube” for gem diamonds. We have not documented the intermediate conditions between these two extremes in the Sunagawa diagram...

...Donald J. Lake; Lee A. Groat; Hendrik Falck; Thomas Mulja; Jan CempÍrek; Daniel Kontak; Daniel Marshall; Gaston Giuliani; Mostafa Fayek Abstract Emerald at the Lened occurrence in the western Northwest Territories is hosted by quartz veins cutting skarn near the Lened granite pluton and older...

...Stefano Salvi; Gaston Giuliani; Prosper Rakatovao Andrianjakavah; Bernard Moine; Didier Beziat; Anthony Fallick Abstract The Ianapera emerald deposit is hosted in the Neoproterozoic Vohibory domain of southern Madagascar, within a tightly folded metamorphic sequence of mafic and ultramafic rocks (M...

... by Pliny the Elder in his Naturalis Historia (Books 37, 37; 37, 59), he proposed the term émeraude garamantique , the Garamantian emerald ( Duveyrier 1864 ). This term, however, does not refer to emeralds in the modern sense (a green variety of beryl), which were probably unknown to the Garamantes...

...Dan Marshall; Nicolas Meisser; Sarah Ellis; Peter Jones; François Bussy; Thomas Mumenthaler Abstract Emerald from the Binntal occurrence in the Canton of Valais in Switzerland has been studied to determine its chemical zonation, stable isotopic signatures, depositional-fluid characteristics...

...Isabella Pignatelli; Gaston Giuliani; Christophe Morlot; Olivier Rouer; Nicolas Claiser; Pierre-Yves Chatagnier; David Goubert Abstract Colombian euclase is rare and associated with emerald in medium-temperature hydrothermal veins hosted by Lower Cretaceous black shales (BS). The original sources...

...J.E. Lum; K.S. Viljoen; B. Cairncross Abstract The world’s oldest emerald deposit occurs in the Gravelotte-Leydsdorp area of the Limpopo Province of South Africa. Emeralds have been mined from the main emerald working, the Cobra pit, since 1927, although emeralds were discovered in the area much...

... observed for the natural beryl in the range of the OD stretching vibrations have been explained. * E-mail: rim@igm.nsc.ru Manuscript handled by Ian Swainson 21 5 2015 21 7 2015 © 2016 Mineralogical Society of America 2016 Beryl emerald FTIR spectroscopy H 2 O, D 2 O...

...Nadège Ollier; Yves Fuchs; Olivier Cavani; Adolf Heinrich Horn; Stéphanie Rossano Abstract Emerald and alexandrite, the chromiferous varieties of beryl, Be 3 Al 2 [Si 6 O 18 ], and chrysoberyl, BeAl 2 O 4 , respectively, are, as gems, of high economical and technological interest. The Cr 3...

...G. Raade; T. Balić-žunić; C. J. Stanley Abstract Byrudite (IMA 2013-045, Raade et al ., 2013 ), with simplified formula (Be,□)(V 3+ ,Ti) 3 O 6 , occurs in emerald-bearing syenitic pegmatites of Permian age at Byrud farm, Eidsvoll, Akershus, South Norway. It has a norbergite-type structure, Pnma...

...E. P. Lynch; A. Costanzo; M. Feely; N. J. F. Blamey; J. Pironon; P. Lavin Abstract New fluid inclusion analyses using a range of analytical techniques including quadropole mass spectrometric analyses coupled with gemmological investigations were conducted on rough and gem-quality faceted emeralds...

...M.L. Hewton; D.D. Marshall; L. Ootes; L.E. Loughrey; R.A. Creaser Abstract Emerald in the Mackenzie Mountains is hosted in extensional quartz–carbonate veins cutting organic-poor Neoproterozoic sandstones and siltstones within the hanging wall of a thrust fault that emplaced these strata above...

..., and gemstock is recovered by breaking out clear portions from the crystals. Emerald (the grass green, Cr- or Cr–V-rich variety of beryl) and alexandrite (the Cr- or Cr–V-rich variety of chrysoberyl) in “Urals-type” deposits, such as those in the Ural Mountains of Russia, the Kafubu area of Zambia...

...D. Marshall; V. Pardieu; L. Loughrey; P. Jones; G. Xue Abstract Preliminary geological work on samples from Davdar in China indicate that emerald occurs in quartz veins hosted within upper greenschist grade Permian metasedimentary rocks including quartzite, marble, phyllite and schist. Fluid...

...Mohammad Arif; Darrell J. Henry; Charlie J. Moon Abstract Carbonate-talc altered ultramafic (and mafic) rocks of the obducted oceanic lithosphere along the Main Mantle Thrust in the Swat Valley host emerald deposits and are invaded by quartz veins and stockworks. Both the quartz veins and carbonate...

...G. Xue; D. Marshall; S. Zhang; T. D. Ullrich; T. Bishop; L. A. Groat; D. J. Thorkelson; G. Giuliani; A. E. Fallick Abstract The Dyakou emerald occurrence is located in Malipo County in the province of Yunnan, southern China. The occurrence lies in the northern part of the Laojunshan-Song Chay...

...Christopher G. Galbraith; D. Barrie Clarke; Robert B. Trumbull; Michael Wiedenbeck Abstract Tourmaline is ubiquitous at the Tsa da Glisza emerald prospect, Yukon Territory, occurring as porphyroblasts in greenschistfacies metavolcanic and ultramafic rocks and as crystals in granites, aplites...