Valley of the Gems

Author Ted Themelis has written a book about the most famous of gem localities, the Mogok (Burma) ruby and sapphire mines. Mogok, Valley of Rubies & Sapphires is a colorful account of a region that few have visited but almost everyone knows because of its rubies.

Themelis, a resident of Bangkok, Thailand, is a gemologist who develops and manufactures gem-testing equipment and experiments in gemstone enhancements, primarily corundum heat treatment. In 1995, he produced the first electric resistance furnace for heat-treating ruby and sapphire.

He also has published more than 120 articles on gem identification, instrumentation, treatments, and other gemological topics. He is probably best known for writing The Heat Treatment of Ruby and Sapphire (1992), the only book that deals exclusively with this subject.

The nine chapters in Mogok, Valley of Rubies & Sapphires address topics such as Mogok’s history, an examination of the mine and the people who work there, and how gems are traded. It also looks at some notable Mogok gems and features more than 600 images.

Bear Williams of Bear Essentials, a colored stone wholesaler in Jefferson City, Mo., calls it “the most consummate and unrivaled book on the history, life, and inner beauty of the Mogokian people” and says the pictures alone make the book “a must-have treasure.”

For more information on Mogok, Valley of Rubies & Sapphires, contact Ted Themelis at, or visit his Web site at