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

Diamond is the only gem made of a single element: It is typically about 99.95 percent carbon. The other 0.05 percent can include one or more trace elements, which are atoms that aren’t part of the diamond’s essential chemistry. Some trace elements can influence its color or crystal shape.

Diamonds have a long history as beautiful objects of desire. In the first century AD, the Roman naturalist Pliny stated: “Diamond is the most valuable, not only of precious stones, but of all things in this world.” A diamond has to go through a lot before it reaches the jeweler’s display case.

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. With an unbiased diamond evaluation, you’re free to focus on its beauty.

A well-cut diamond displays the beauty consumers expect to see in a diamond. A beautiful diamond looks the way it does because of three optical effects: white light reflections called brightness, flashes of color called fire, and areas of light and dark called scintillation.

2024年5月3日 · Diamond is a much more compact form of carbon, with a density of 3.52 g/cm 3, 56% higher than the density of graphite. Great confining pressure is required to stabilize the denser configuration of carbon atoms and crystallize …

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 information, uniform practices, scientific grading and transparent evaluation in the global diamond industry.

2024年12月2日 · Diamond’s remarkable properties—including high hardness, high thermal conductivity, low thermal expansion, wide optical window, biocompatibility, and high resistance to corrosion, acid, and radiation—have a wide range of engineering applications.

From the Hope diamond to the Spirit of the Rose, the Taylor Burton and the Lesotho Promise, we are trusted by museums and top auction houses all over the world to grade and research nature’s finest treasures.

The correct way to evaluate diamond color is in precise conditions, under controlled lighting, where stones are compared to masterstones with established color grades. Once properly evaluated, color is documented based on the GIA D-to-Z Color Scale.