Abstract

Gemmological characteristics of corundum from host rocks (gneiss migmatite, pegmatoid) in the Trúc Lâu area, Lục Yên District, Yên Bái Province, have been examined and compared with the ones from placer in order to determine the source supplying gemstone to the Trúc Lâu placer mine. The results indicate that there are at least two sources: metapelite and marble. The second source needs further investigations. Corundum from metapelite has low gem quality while the one from marble is of higher quality.