Get to know all you need about diamond – the history, facts, quality factors, treatments, imitations and much more here at GIA.

The 4Cs describe the individual qualities of a diamond, and the value of an individual diamond is based on these qualities. The terms that people use to discuss the 4Cs have become part of an …

what's in a name? Diamond [dye -mund] (noun) Diamond comes from the Greek word adamas which means “invincible.” For being the hardest material on earth, that is the perfect name for this gem!

While choosing a diamond is a very personal decision, evaluating a diamond should always be a matter of precision. At GIA, we are incredibly proud that our 4Cs of diamond quality continue to educate the …

It isn’t until a diamond is cut, that the real beauty of a diamond begins to take shape. With a GIA Diamond Grading Report, you can confidently make your next diamond purchase.

Nov 21, 2025 · Explore the GIA Guide to Diamond Engagement Ring Shapes and learn the differences between round, oval, marquise and more. Make a well-informed decision when choosing the perfect …

Mar 14, 2013 · The prospect of purchasing a diamond may seem daunting, but through GIA, an unbiased authority on diamonds, you have several handy resources to help you select the highest …

Jul 9, 2014 · In the 1930s, scientists first began to use two categories to describe a diamond’s chemical composition and atomic structure: type I and type II. Now these categories are further subdivided into …

Fancy Color Diamond Dazzling brilliance. Captivating color. These are the planet’s most valued gems.

Presents the first scientific and historical study conducted on the 2.33 ct Winston Red, the fifth-largest known Fancy red diamond in existence.