Gem-quality rubies and pink to purple sapphires are being recovered from the Luc Yen and Quy Chau mining regions of Vietnam. This article briefly reviews the history and geology of these areas, as well as the mining methods used. The gemological characteristics of more than 100 of these stones are described in detail. The most notable internal features are blue color zones, swirl-like and angular growth features, bluish "clouds," and inclusions of rod-like calcite and pyrrhotite as well as the rare mineral nordstrandite.
Gem-quality rubies and pink to purple sapphires are being recovered from the Luc Yen and Quy Chau mining regions of Vietnam. This article briefly reviews the history and geology of these areas, as well as the mining methods used. The gemological characteristics of more than 100 of these stones are described in detail. The most notable internal features are blue color zones, swirl-like and angular growth features, bluish "clouds," and inclusions of rod-like calcite and pyrrhotite as well as the rare mineral nordstrandite.