Certificates And Diamond Identification

A major purpose of diamond certification is to have documentation confirming the jewel’s quality. Certificates are also useful in helping to distinguish one diamond from another. While each diamond has distinct features, they may require careful analysis to determine what they are. A report can serve as a reference that experts and laypeople alike can understand.

Sometimes the differences between two stones is apparent. Shape, size, color or clarity may be drastic enough that a glance is all that’s needed to pinpoint a certain stone. Distinctions can also be subtle, such as two round brilliants of similar weight to the hundredth of a carat. Rather than giving a jewel a lengthy inspection each time to determine its identity, certification outlines a jewel’s distinctive features in an easy to read and verify format.

When a diamond is graded by the Gemological Institute of America (GIA,) it’s weighed to the fifth decimal place for optimal accuracy before being rounded to the second decimal. The stone’s height, weight and depth is measured to the hundredth of a millimeter. A sketch of the diamond outlines its table size, pavilion depth, crown height and other angles and proportions particular to that stone.

Other factors examined during grading include clarity and color. Most diamonds fall on a color scale of D to Z, with D being completely colorless and Z having the most visible tint. While some hues are rarer than others, a specific grade can help narrow which jewel is which. With clarity, no two diamonds have the same characteristics. Inclusions and blemishes are marked on a diagram for easy identification.

Each diamond graded by GIA is given a unique ID number. This is listed at the left as well as the top center of the report. The number can serve as a one point reference for those who need to quickly distinguish between diamonds.

An optional step in GIA certification diamond is to have the diamond’s ID number inscribed on the girdle, or outermost perimeter of the diamond. The number is small and does not impact the jewel’s appearance or clarity grading. It also directly connects the diamond with its report, allowing it to be verified even if the certificate is not immediately available.