Fine-color, large, and eye-clean (lacking visible inclusions) rubies like this 11.01carat (ct) stone from Myanmar (formerly known as Burma) are extremely rare and valuable. – Photo: Robert Weldon/GIA.

This 5.30-carat emerald from Brazil has a slightly bluish green color. Courtesy John Parrish, courtesy African, Brazilian, Colombian Gems Incorporated. Emerald has many special qualities, but colored ...

The 330-ct Star of Asia is in the collection of the National Museum of Natural History – Chip Clark, courtesy Smithsonian Institution Traditionally, sapphire symbolizes nobility, truth, sincerity, and ...

As a consumer, you will regularly encounter in the marketplace gems that have been treated to change their appearance. A topic that often comes up is whether a particular gemstone is or isn’t treated.

Diamond is available in a range of sizes and qualities to fit every consumer's tastes. One of the first things most people learn about diamonds is that not all diamonds are created equal. In fact, ...

Cultured pearls come in different sizes, shapes, and colors. Perhaps the best-loved gems of all time, pearls—both natural and modern cultured pearls—occur in a wide variety of colors. The most ...

You need access to the trusted data that appears on GIA grading and analysis reports in a reliable and secure manner. Customers today demand that the information they use to inform their purchasing ...

This 146.10-carat peridot is in the collection of the Natural History Museum in London Peridot has always been associated with light. In fact, the Egyptians called it the “gem of the sun.” Some ...

No peridot is known to be heated to improve its appearance. Although the claim is technically true, it’s misleading.

Figure 1. A single tourmaline fiber contains three distinct chemical zones, each recording the fluid composition at the time of growth. Between zones, fluids dissolved preexisting tourmaline to ...

The green turquoise cabochon, from an American mine, might become part of a designer’s unique jewelry piece. The even blue color of the cabochon on the right would be called “Persian blue” in the ...

If you were born in February, your birthstone is amethyst – the purple variety of quartz that has captivated mankind for millennia. Its lilac to deep purple hues can be cut into many shapes and sizes, ...