 | | Journal (article/letter/editorial) | | characteristics of emeralds from the Leydsdorp area, South Africa J.E. Lum, K.S. Viljoen and B. Cairncross Department...Johannesburg, P.O. Box 524, Auckland Park, 2006, South Africa. e-mail: jullieta.lum@gmail.com; fanusv@uj.ac...Society of South Africa 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...the Cobra pit, since 1927, although emeralds were discovered in the area much earlier. The emerald mineralisation |  | | Journal (article/letter/editorial) | | during emerald mineralization at Gravelotte, Murchison Greenstone Belt, Northeast Transvaal, South Africa...evolution during emeraId inception at the Gravelotte emerald mine has been studied by mi~~e~ornet~ and laser...respectively, 250, 150, and 24O”C, and pressures in the range of l-4 kb. Calculations of fo,show an initial low...In the later stages, phenakite was converted to emerald as alumina activities in the system increased....me~mo~hism. THE GRAVELOTTE AREA LIES along the southern margin of the Archean Murchison Greenstone Belt |  | | Journal (article/letter/editorial) | | EconomicGeology Vol. 84, 1989, pp. 1835-1849 Emerald Mineralization during RegionalMetamorphism'The...studiesof the I-Iabachtal(Austria)and Leydsdorp(South Africa) emeralddepositsindicatethat the emeraldformationwasnot...0361-0128/89/997/1835-15$3.00 p.96) on the famousTakowaja emerald depositsin the Ural Mountains(USSR):"It is now...MORTEANI Petrologicand geochemicalstudiesof the emerald interlayeredserpentiniteswhichis calledthe Habach...(lower schistcover) which is interpreted as The local emeraldsformed during regional metamorphismin an |  | Giuliani, G., France-Lanord, C., Coget, P., Schwarz, D., Cheilletz, A., Branquet, Y., Giard, D., Martin-Izard, A., Alexandrov, P., Piat, D. H. (1998) Oxygen isotope systematics of emerald: relevance for its origin and geological significance. Mineralium Deposita, 33 (5) 513-519 doi:10.1007/s001260050166 | Journal (article/letter/editorial) | | Alexandrov á D. H. Piat Oxygen isotope systematics of emerald: relevance for its origin and geological signi®cance...composition of emerald from 62 occurrences and deposits in the world reveals a wide range in d18O (SMOW)...the origin of emerald from the world's most important producers. The d18Ovalue of emerald appears to be...quality from Colombia (eastern emerald zone, d18O +16.8 0.1&; western emerald zone, d18O +21.2 0.5&)...5 0.5&). Furthermore, the 18O-composition of emerald appears to be a good marker of its geological environment |  | | Catalog/List | | RAINBOW OF AFRICA GEM & MINERAL COLLECTION Front Cover: Gems from the Rainbow of Africa Collection... Heritage Signature® Auction #5236 The Rainbow of Africa Collection Gems & Minerals October 15, 2015 | New...Signature® Internet Session 2 Heritage Auctions Design District Annex 1518 Slocum Street • Dallas, TX 75207 (HERITAGELive...RAINBOW OF AFRICA COLLECTION You have in front of you our presentation of the Rainbow of Africa Collection:...The mineral riches of Africa are not the only things making up the Rainbow of Africa Collection. For the |  | | Report (volume) | | extensive explora¬ tion of the mountains north and south of the Kashmir Valley and in the upper basin of...that the trappean rocks must belong to a period of local eruption in the iqipcr part of the Silurian series...pene¬ trate these strata, or above them. On the south-ea.stem prolongation of the Kashmir synclinal, ...in Kistwar and Badriwar, there is in the Pangi district, on the ujiper Chenab, a smaller symclinal ellipse...Lahul. in which only This basin is cut off to the south-east by This feature of longitudinal I’ecurrence |
|
