Synthetic moissanite is much closer to diamond in overall appearance and heft than any previous diamond imitation; this article reports on how to identify and characterize it.

View the holiday schedule for all GIA locations worldwide.

The island of Borneo is one of the oldest known —and least reported on—sources of diamonds. Although diamond mining historically was concentrated in the western area of what is now Kalimantan, recent ...

While more people are becoming familiar with lab-grown diamonds, many still don’t know how they are actually made. Learn about the two diamond growth processes, HPHT and CVD.

Shows how the color of Madagascar sapphire is lightened with heating to relatively low temperatures below 1350°C.

To give objects a futuristic look, Art Deco artists used vertical lines and geometric shapes (arcs, circles, triangles, squares, rectangles, etc.) in repetitive patterns. The Chrysler Building in ...

Diamonds have a long history as a premier gemstone—a natural consequence of their beauty, rarity, and superlative physical properties such as extreme hardness. Diamonds that are mined for use as ...

Natural pearl identification is one of the critical problems in pearl research. The DNA study of pearly mollusks and oysters facilitates solving this problem. To fulfill this goal, GIA sent a group ...

What exactly are man-made diamonds? Find out how they compare to natural diamonds and what you should know.

Learn more about what causes a diamond to chip, and 8 tips on how you can avoid chipping your diamond.

How – and where – you look at your diamond can greatly change its appearance.

Figure 1. This purplish pink diaspore is reportedly from a new deposit in Afghanistan, discovered in February 2020. The faceted stones weigh 0.57 to 1.60 ct; courtesy of Donald Hofler. The rough ...