Most people ask, What is a Laboratory Certificate and why are they so important? Most often they are confused with an insurance appraisal. While some of the information that is needed for an insurance appraisal is found on a laboratory certificate they are two completely different things.
A laboratory certificate is prepared by a gemological trade laboratory as an unbiased third party grading of a specific diamond. An appraisal, on the other hand, is usually prepared by the company that sold the diamond and is intended for use by the owners insurance company for purposes of insuring the diamond against theft, loss or damage.
Take a few moments and watch this video to the right created by the non-profit Gemological Institue of America.
To be an educated consumer you should really have both. The laboratory certificate tells exactly the quality of the diamond. The insurance appraisal gives it the corresponding value. Laboratory certificates do not provide a value. Without a laboratory certificate it is common in the jewelry industry for appraisals to give the "benefit of the doubt" when grading diamonds. This usually means that they are graded higher in quality than they really are. The accuracy of an appraisal is relatively unimportant until the diamond is lost or stolen.The irony is that once the diamond is lost or stolen, it is no longer there to dispute the grading!
The real problem is that most people base their decision when purchasing a diamond on the grading that will appear on the appraisal. The difference between what an appraisal says and what a diamond really is can be considerable. This can cause a dramatic inflation of the perceived value of a diamond. In many cases the value will vary from 20% to 100% or more due to improper grading on non-certified diamonds.
There are a number of reputable Gemological Institutes around the world that will issue certificates for a specific diamond. In the United States the top three are listed below.
There is clearly one laboratory however, that is revered as the worlds finest, The Gemological Institute of America. In 1931, the GIA created the grading system that is used internationally for grading diamonds. This non-profit educational reserarch institution is committed to expanding our knowledge of gemmology and safeguarding the industries ethical standards.