American Gemological Laboratories (AGL)
New York, United States
Specialty: Coloured stones, origin reports
Gem laboratories
Laboratories that test and grade diamonds, coloured stones and pearls, and assay offices that test precious metals, around the world.
Americas
CDTEC GemLab
Bogotá, Colombia
Specialty: Emeralds, coloured stones, diamonds; treatment and origin
Gem Certification & Assurance Lab (GCAL)
New York, United States
Specialty: Diamonds
Gemological Institute of America (GIA)
Carlsbad, United States · also New York, Mumbai, Surat, Bangkok, Hong Kong, Tokyo, Ramat Gan, Antwerp, Gaborone, Dubai
Specialty: Diamonds, lab-grown diamonds, coloured stones, pearls
Gemological Science International (GSI)
New York, United States
Specialty: Diamonds, lab-grown diamonds, gemstones
Listed alphabetically within each region. JewelLoop does not rank, recommend or endorse any laboratory. Details come from each laboratory's own website; check services and fees with the laboratory directly.