Business

Provides diamond grading services featuring grading of the diamond cut.

Providing analysis, reports, and supporting services for diamonds, colored diamonds, colored gemstones, pearls, and mounted jewelry. Operating exclusively in North America.

Offers gem grading and identification services and courses for the trade and members.

Determination of the authenticity and country of origin of a rubies and sapphires. Offers gemstone reports and inscriptions.

Independent service provides general information on gemstones, ongoing research and lab report services.

Fine jewelry appraisals by an independent team. Services, price list, and location map. In Manchester, CT.

Offers gemstone analysis software, gemological education, and gemological laboratory services. Includes articles on diamond cut studies and a gallery of virtual diamond images.

An independent, international, non-profit organisation dedicated to the identification, treatment, and origin. Services, education, and contact information. Located in Switzerland.