Certification is proof of a diamond’s 4C’s grading

Although many diamonds look similar, they are not all of equal quality. Diamond certification is the written proof of a diamond’s attributes. It’s your assurance that the diamond’s value is worth the price you are paying.

Diamond certification provides the precise grading for each of the 4C’s – carat weight, cut, color and clarity. With this certification in hand, you have the information you need to assess a diamond’s fair market value and price. It also allows you to make informed comparisons with other diamonds, either in the same jewelry store or in another, so you can better understand the differences in value and price.

Diamond certificates are issued by independent gemological laboratories. There are several grading laboratories, two of the most prominent being:

  • Gemological Institute of America® (GIA)
  • Gemological Science International® (GSI)

All THE LEO® Diamond, THE LEO Ideal Cut® Diamond and THE LEO First Light® Diamond solitaires, engagement rings and anniversary bands at Kay Jewelers receive GSI certification. THE LEO First Light ®Diamond solitaires and loose diamonds at Jared receive GIA certification .

Another aspect of the inherent beauty of a diamond is its brilliance. Certification from GemEx® Systems—the global leader in brilliance certification--verifies the “Return of Light” — the level of brilliance your diamond achieves. The GemEx® BrillianceScope™ measures the percentage of white light, colored light and sparkle that a diamond returns, and the number of points of light that turn on and off as the diamond moves.

THE LEO Diamond® was the first diamond ever independently and individually certified by GemEx® to be visibly brighter. As proof of the superior brilliance of THE LEO® Diamond, every solitaire engagement ring and bridal center diamond featuring THE LEO® Diamond is guaranteed to score at least two “VERY HIGH” ratings on the Light Performance Report. All other jewelry from THE LEO® Diamond Collection is guaranteed to score a minimum of three “HIGH” ratings on the Light Performance Report.

When you buy a certified diamond from a trusted jeweler, ask to see the diamond certification reports that will accompany the diamond when you purchase it.


Authorized jewelers who offer THE LEO Collection of diamonds encourage you to compare our brilliance with other diamonds through a diamond microscope or an in-store interactive tablet, so you can see the difference for yourself.

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