About Gemlab

Gemlab was founded in 1975 by Ted Themelis and it is operated by his family. The company has experienced many phases in the gem & jewelry industry Including gem trading, manufacturing of gem instruments, research & development projects, gem treatment services and fabrication of high-temp. furnaces with gem treatment installations around the globe.

For over thirty years, Gemlab continues to provide dependable and accurate services to our selected clients.

Our focus is dedicated to quality, accuracy, service and speed. Our services are designed to help solve problems, support research & development, and provide guides for quality and assurance control. The following equipment are installed in our gem treatment lab and used in our applications and projects, as well as for training our students:

3 High-Temp (1800 ํC) electric muffle furnaces
3 Low-Temp (1100 ํC) electric muffle furnace
1 High-Temp (1800 ํC+) LPG-OXY combustion furnace
1 High-pressure-low temp. hydrothermal capsule-vessel
2 High-pressure, low-temp (10,000 psi, 250 ํC) apparatus

About Ted Themelis

Ted Themelis received his Bachelor of Science degree from the City University of New York in 1975. He has worked extensively in development, engineering, and manufacturing of innovative gemological testing instruments & apparatuses. Since 1979, he has been i involved in various experimental gemstone enhancement projects, primarily in the heat treatment of ruby-sapphire.

He has traveled extensively, to the most inaccessible gem mining areas in Burma, Sri Lanka, Thailand, Vietnam, India, Pakistan, Afghanistan, Nepal, Tanzania, Kenya, S. Africa, Venezuela, Colombia, Brazil, China, and elsewhere. From 1984-1986, he served as Director of Research &Development of the Accredited Gemologists Association in the USA. He is the author five books; The Heat Treatment of Ruby & Sapphire (first, second edition), Beryllium Treated Rubies & Sapphires, Flux-enhanced Rubies & Sapphires, Mogok-Valley of Rubies Sapphires, Gems and Mines of Mogok. He has published over 120 articles on gem identification, instrument ion, treatments, mining, inclusions and other subjects.

In 1995 he produced the first electric resistance 1800 ํC furnace on the market, using MoSi2 Kanthal Super 1900 ํC grade heating elements with full atmospheric control, specifically designed for the heat-treatment of ruby and sapphire. In 2006 he was nominated for the prestigious Bononno Award of Gemological Excellence.

He maintains state-of-the-art gemstone treatment laboratory in Thailand providing gem treatment technology, equipment, and services to the gem and
jewelry industry. In his workshop in Bangkok he fabricates high temperature, high quality, innovative furnaces and special gemological LED microscopes.

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