Gems & Gemology, Summer 1994, Vol. 30, No. 2
Update on Mining Rubies and Fancy Sapphires in Northern Vietnam
Robert C. Kammerling, Alice S. Keller, と Kenneth V. Scarratt, Saverio Repetto
Northern Vietnam began producing significant quantities of rubies and fancy sapphires in the late 1980s. Since then, mining has evolved at the two major producing areas: Luc Yen and Quy Chau. Heavy machinery is now used in both of these remote areas, but small-scale manual mining is ongoing. Efforts continue to establish organized cutting and distribution centers.