diamond labs

Reporting From the Rapaport Conference: What Consumers Need to Know About Gem Labs

Filed under: Jewelry

When you buy a diamond you get hit with a lot of letters and numbers. VS, SI, F color, etc. But who determines what number goes with what diamond? With diamonds the grading for color and clarity is a major determinant in price. Unfortunately it's also a way that the unscrupulous can capitalize on the unsuspecting. Have you ever seen an ad where the jeweler promises that the stone will appraise for more than the sale price? How can that be? In some cases, jewelers use labs that are cheaper and/or have more open standards. This issues was discussed by a group of diamond jewelers, merchants and other concerned people at the Rapaport Conference on Diamond Certification on June 6 at the JCK Las Vegas show.

One stone can get two different grades from two different labs. There is no absolute standard for diamond grading, it always comes down to the decision of the grader. The Gemological Institute of America created and determined the standard in the 1950s but any lab can grade stones using the same nomenclature and consumers may not be aware that there is any difference between the standards of grading labs. The GIA naming standards are not patented and can be used by any lab and have created a common language through which to discuss diamond quality. But it may be misleading to the consumer if labs which do not use the GIA grading standards use the GIA nomenclature.

This has led to a situation where there are price differentials in certificates. Is the same diamond worth more with a certification for a different lab? Some labs have a reputation for being more lenient. This is something that jewelers and diamond buyers know but not something that is clear to the consumer. The GIA charges more for certification and is known to be stricter.

Tags: diamond, diamond grading, diamond labs, diamonds, martin rapaport