Research Article Search Results

Blue diffusion-treated sapphires have become a subject of considerable controversy since their introduction in significant quantities a few years ago.

Burma, now named Myanmar, has for centuries been considered the world's preeminent source of fine rubies.

The Coscuez mine, one of a number in Colombia, is rapidly gaining significance as a major source of fine emeralds.

A review of the history of this area, its geology, and the mining methods that have predominated.

This article focuses on Colombian emeralds and gives a detailed explanation of the oiling process as observed by the author.

Thailand has become the world's major source of gem ruby.

A comprehensive review of the history and geology of Colombian emeralds together with descriptions of some of the most famous gems to come from this locality.