The Gemological Institute of America (GIA) is a nonprofit organization that is widely recognized as one of the world's foremost authorities on diamonds, colored stones, and pearls. Founded in 1931, the GIA's primary mission is to protect buyers and sellers of gemstones by setting and maintaining the standards used to evaluate gemstone quality.

GIA® is short for the Gemological Institute of America.

No, GIA® neither sells nor certifies diamonds. The institution only grades and gives unbiased assessments of diamonds. However, GIA® graded diamonds may be purchased from certified retailers.

Certified GIA® retailers, like Hamilton, carry GIA® graded diamonds and/or have a GIA®-trained staff. This means that all diamonds purchased from these certified retailers have the unbiased, scientific assessment evaluating and proving a diamond’s quality and value, allowing buyers to be confident in their purchase.

Using the 4C’s of diamonds, a universal system created by GIA® to simplify the grading process worldwide, GIA® protects buyers of diamonds. The accurate, professional, and unbiased grading gives a buyer confidence in their purchase.

The 4C’s are: cut, color, clarity, and carat.

A diamond grading report is the best credential of a diamond’s authenticity and quality. Each report includes an assessment of the 4C’s, as well as a plotted diagram of clarity characteristics and a graphic representation of the diamond’s properties. Furthermore, the report will denote any treatment that was previously made to enhance clarity or color or clarity.

A grading report is not an appraisal of a diamond, nor is it a certification. A report is a blueprint of a diamond’s exact characteristics and quality, like the architectural blueprints of a house. A GIA® grading report assures the buyer that the diamond they are purchasing, or already have in their possession is natural.

The best way to get your report is to bring your diamond to a fine jewelry retailer. Retailers, like Hamilton, are exclusively qualified to obtain a report and explain it to the customer upon completion. Please be aware that diamonds will have to be taken out of their settings in order to undergo assessment.

GIA® employs hundreds of professional diamond graders, gemologists, and research scientists, ensuring that diamonds are checked and cross checked by a number of trained experts before a report is made.

Diamonds that GIA® can grade are loose, natural diamonds in the D-Z color range, weighing 0.15 carats or more. Laser drilled diamonds are acceptable, but note that the report will indicate that the diamond has been treated.

GIA® cannot give a grading report for synthetic diamonds, diamond stimulants, mounted diamonds, or those that have undergone treatments, such as filling or coating.

Calculating cost for a grading report goes by weight. For diamonds weighing 0.70ct to 0.99ct the price begins at $48. Diamonds weighing 1.00ct to 1.49ct can expect to pay a minimum of $80.