Long P. V. auteur aut IRD Pardieu V. auteur aut IRD Giuliani Gaston auteur aut IRD text journalArticle eng text/pdf born digital access In 1987, gems were discovered in the Luc Yen area of Vietnam's Yen Bai province. Ruby, sapphire, and spinel from primary and secondary deposits are the most valuable of these; tourmaline, gem-quality feldspar, pargasite, and humite are also mined there. As a result of this discovery, the Luc Yen district has become Vietnam's most important gemstone-trading center over the past 30 years. The markets of Yen The, the capital of Luc Yen, offer an additional assortment of natural gems from Vietnam and elsewhere (including peridot, beryl, aquamarine, topaz, and quartz); synthetic gems are also found in these markets. specialized VIETNAM 064 49 4 233-245 2013 0016-626X https://www.documentation.ird.fr/hor/fdi:010061762 10.5741/gems.49.4.233 0016-626X [F B010061762] https://www.documentation.ird.fr/hor/fdi:010061762 https://www.documentation.ird.fr/intranet/publi/2014/03/010061762.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2014-04-02 2017-08-23 fdi:010061762 fre