The GUILD Gem Laboratory has become the first laboratory to be stationed in Cairo, Egypt, to provide international colored gemstone consultation services. Since then, the international colored gemstone consultation services of the GUILD Gem Laboratory have been carried out in Ho Chi Minh City, Vietnam (in 2006) and Puerto Vallarta, Mexico (in 2006) respectively.

Charles Carmona, the founder and Chief Gemologist of GUILD Gem Lab, published the book "The Complete Handbook for Gemstone Weight Estimation," which has become an essential guide for professional colored gemstone buyers. This publication demonstrates GUILD's unwavering commitment to continuous exploration in the field of colored gemstones.

Since 1985, GUILD Gem Lab has been a founding member of the International Colored Gemstone Association (ICA) and attended the inaugural ICA annual conference. In February 2023, Ruby Liu, President of GUILD, and Andrew Lucas, Senior Vice President of GUILD, delivered a speech titled "The Development of the Chinese Colored Gemstone Market" at the ICA annual conference.

In April 1980, GUILD Gem Lab was established in Los Angeles, USA. GUILD is an international gemstone laboratory that provides services such as gemstone identification, grading, origin determination, and enhanced treatment detection. To this day, GUILD has laboratories in the United States (Los Angeles), China (Shenzhen, Guangzhou, Zhuji), Thailand (Bangkok), Sri Lanka (Beruwala), and other locations. With a professional, scientific, and innovative spirit, GUILD offers clients professional and reliable testing services.