Global Gem Testing Laboratory Co., Ltd (GGT) is a private, independent gemological laboratory. We provide reliable and accurate gemological testing services. Our quality reports are certified by experienced professional gemologists.

GGT Services

  Distinguishing natural and synthetic gemstones

  Analyzing treatments in gemstones

  Determining the origin of ruby and sapphire

  Analyzing gemstones by advanced instruments

  Grading diamond clarity and color

  Consultation with gemologists