How Can I Tell If the Clarity Rating of a Diamond Is Good?

Check the clarity rating on the certificate that came with your diamond at the time of purchase. Any reputable gemstone vendor will sell stones that have been inspected by the American Gem Society (AGS), the Gemological Institute of America (GIA) or another firm that specializes in grading and certifying gemstones. Diamonds are rated on a scale from "F" (flawless) to "I1-2-3" (there are inclusions in the stone visible to the eye with and without magnification). "F"and "IF" (internally flawless) stones are extremely rare and quite expensive. Stones rated "VSI" or "SI" (very slight or slight inclusions) are widely available and a good buy. Most jewelers will not sell stones that fall into the I1-2-3- rating.

Submit your diamond to the American Gem Society or the Gemological Institute of America for grading and certification. Both of these firms have locations throughout the United States (and, in the case of the GIA, the globe) where your stone can be evaluated and professionally graded. The respective websites for each company contain databases where you can find a location near you. This is the best option if you are looking to sell your diamond and do not have a certificate from the original vendor.

Consult a professional jeweler and ask him to magnify your stone. Most jewelers have been trained to examine diamonds, and can provide feedback on the clarity of your diamond. While a jeweler may be unable to give you an official certificate, he can provide a general idea as to your stone's clarity. For someone looking for second opinion or an informal evaluation, this is a wise choice.

Examine your diamond with the naked eye and with a jeweler's loupe. If you can see a dark spot or flaw with your eyes, chances are you're not purchasing a stone with a high clarity rating.