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Almost everyone has heard of the "4 C's" of diamond value: cut, color, clarity and carat weight. Today, there's a "5th C" called "certification." A diamond certificate, also called a grading report, issued by a major independent gemological laboratory like EGL USA is the best way to assure the quality, authenticity, and integrity of your purchase.


The vast majority of EGL USA certificates are requested by the jewelry trade, however, consumers may send their diamonds, colored stones, or pearls directly to an EGL USA Group office for identification, grading, or laser inscription. Retail jewelers can also make lab service arrangements for you.

EGL USA is one of the largest gemological institutions in the world and grades a high percentage of all certified diamonds in the United States and Canada.


Includes an assessment of a diamond's 4C's – color, clarity, cut, and carat weight – along with a plotted diagram of its clarity characteristics and a graphic representation of the diamond's proportions. For standard round brilliant cut diamonds falling in the D-Z color range, the report also includes a GIA Cut grade.

The GIA laboratory issues diamond grading reports for loose, natural diamonds in the D-Z color range that weigh 0.15 carats or more. GIA Diamond Grading Reports are not issued for synthetics, simulants, mounted diamonds or those that have undergone unstable treatments, such as fracture filling or coating