GUILD was founded in Los Angeles in July 1980. Over the past 40 years, it has always been committed to the research, identification, popularization and promotion of colored gemstones. It has rich experience and massive achievements in the field of constructing the standardization system of colored gemstones market.

Relying on the profound academic research background and a large number of color gem origin research and market identification data, it has built an enterprise database, covering the detection of common gem categories in all markets. Focus, accumulation, cohesion and breakthrough. From the start-up appraisal institutions on the east coast of the Pacific to the authoritative appraisal brands based in the Asia Pacific and radiating around the world, each development node resonates with the international color gem industry