About 220,000 results
Open links in new tab
  1. Natural Diamonds | Diamond Stone – GIA C

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

  2. GIA Diamond Grading Scales: The Universal Measure of Quality

    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 …

  3. Diamond Description

    Diamond forms under high temperature and pressure conditions that exist only within a specific depth range (about 100 miles) beneath the earth’s surface. Diamond’s crystal structure is …

  4. Diamond Quality Factors

    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 …

  5. Home | GIA 4Cs

    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 …

  6. Diamond - Gemological Institute of America

    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 …

  7. How to Buy A Diamond - GIA 4Cs

    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.

  8. Guide to Diamond Engagement Ring Shapes | GIA 4Cs

    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 …

  9. Digging into Diamond Types - GIA 4Cs

    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 …

  10. Understanding the 4Cs of Diamond Quality - GIA 4Cs

    This framework is both a way to better understand your diamond, and to ensure accuracy in the evaluation of your diamond’s unique characteristics. It is the best way to ensure clear …