How GIA Grades Diamonds

How GIA grades Diamonds

Triple Redundancy

Grade it. Grade it again. And then grade it again.
Diamonds submitted for Diamond Grading services are examined by a minimum of four highly-trained and experienced diamond graders and gemologists. At each subsequent grading step, the diamond is independently examined by a more-senior staff member.

Inspection, Care, and Handling Procedures

At every step of the servicing process, special inspection, care, and handling procedures are in place to confirm a diamond’s identity and ensure the diamond is managed with the utmost care.


Client anonymity during the grading process is essential. Almost immediately after the diamond is received, it is placed in a custom-designed, transparent storage case, and all reference to the submitting client is removed.
Client information is completely masked within the software diamond graders use to enter their assessments. This information is only attached to the diamond when the item is matched with its corresponding report and prepared for return to the client. Inventory Control and Routing.

Random Doesn’t Just Happen.

There’s a system, a science, and an entire department dedicated to it. The Inventory Control Department serves as the hub for Laboratory operations. Between each and every step of the grading process, a diamond is distributed from and returned to this department, ensuring that the distribution of diamonds to graders is completely random.

Inventory Control and Routing

This is just one critical step in an independent and impartial grading process. Every diamond or gemstone is tracked electronically so that the Laboratory can pinpoint its exact whereabouts at any time and view and review each step during the grading process.
To say that the laboratory’s routing and inventory control measures are meticulous is something of an understatement.
With thousands of diamonds and hundreds of diamond graders, the routing and tracking of the Laboratory’s inventory requires a highly-trained and alert staff, combined with the best support technology can offer.