 | | Journal (issue) | | Synthetic Diamonds Reversible Color Alteration of Blue Zircon Sapphires from the Russian Far East Grandidierite...are available for group subscriptions, GIA alumni, and current GIA students. To purchase print subscriptions...Return undeliverable copies of Gems & Gemology to GIA, The Robert Mouawad Campus, 5345 Armada Drive, Carlsbad...article in this issue describes how exposing blue zircon to long-wave UV radiation causes them to turn brown...modification can be reversed. The 7.95 ct blue zircon ring on the cover is set in 18K white gold and |  | | Journal (issue) | | Tanzania with phenakite inclusions|Clinohumite from Vietnam|Lace opal from Utah, USA|Pollucite from Pakistan...polylithionite inclusions|Large ruby matrix from Lu.c YĂȘn, Vietnam|Scapolite from Badakhshan, Afghanistan|Tourmaline...Heat Treatment of Gem-Quality Zircon from the Central Highlands of Vietnam By Le Thi-Thu Huong, Bui Sinh...âblackâ axinite. Photomicrograph by N. Renfro, © GIA; image width 1.8 mm. in an area of one stone containing...Nathan Renfro Gemological Institute of America (GIA) Carlsbad, California, USA Reference Gaines R.V |  | | Journal (issue) | | there is new information on gems from Myanmar, Vietnam, Sri Lanka and Siberia. The first paper deals with...(Moon and Phillips, 1994), sapphires from southern Vietnam (Smith et al, 1994), rubies from the Mong Hsu mining...example Australia, Cambodia, Thailand, southern Vietnam, etc.) than in non-heat-treated rubies or sapphires...and Repetto, S., 1994. (Sapphires from southern Vietnam. Submitted for publication.) Suhner, B., 1979....grading scales are available. We also issue CIBJO and GIA reports. FANCY COLOURED DIAMONDS We determine whether |  | | Journal (article/letter/editorial) | | te Xenotime-(Y) Zincite Zinckenite Zinnwaldite Zircon Zoisite (ortho/clinozoiste) Zunyite Bi2Te2S (Cu...rock-forming mineral besides microcline, biotite, calcite, zircon, aegirite, pyrochlore and apatite. Duricrusts containing...ChĂ©telat (1947). of the garnierites of the Uralian province are of hypogene rather supergene origin (chrysotile...The ilmenite and titaniferous magnetite Rogaland province in Norway comprises large anorthosites and associated...or mined as a byproduct (Sn, Fe, REE (monazite, zircon)). Rutile-enriched ilmenite-dominated beach placer | | | Journal (article/letter/editorial) | | te Xenotime-(Y) Zincite Zinckenite Zinnwaldite Zircon Zoisite (ortho/clinozoiste) Zunyite Bi2Te2S (Cu...rock-forming mineral besides microcline, biotite, calcite, zircon, aegirite, pyrochlore and apatite. Duricrusts containing...ChĂ©telat (1947). of the garnierites of the Uralian province are of hypogene rather supergene origin (chrysotile...The ilmenite and titaniferous magnetite Rogaland province in Norway comprises large anorthosites and associated...or mined as a byproduct (Sn, Fe, REE (monazite, zircon)). Rutile-enriched ilmenite-dominated beach placer |
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