Tanzanite is one of the most popular colored gemstones in the world.- Courtesy Tanzanite Foundation ™ Tanzanite is a versatile gemstone that comes in a variety of sizes and cutting styles. Although it ...

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 ...

A synthetic gem material is one that is made in a laboratory, but which shares virtually all chemical, optical, and physical characteristics of its natural mineral counterpart, though in some cases, ...

The world’s love of diamonds had its start in India, where diamonds were gathered from the country’s rivers and streams. Some historians estimate that India was trading in diamonds as early as the ...

Learn about sapphire's durability and how to care for your sapphire jewelry.

Treatment concerns Zircon is commonly heat-treated to produce blue and colorless varieties. As with any transparent gemstone, zircon can be fracture-filled to improve apparent clarity, but this ...

The Graduate Diamonds online diploma coursework is a combination of one online course and one hands-on lab class. Lab classes are offered at GIA campuses worldwide. Diamonds and Diamond Grading - ...

Lapis lazuli is a rock, which means it’s an aggregate of several minerals. This ancient gem contains three minerals in varying amounts: lazurite, calcite, and pyrite. Sometimes, it also contains one ...

The GIA Diamond Grading Report includes an assessment of the 4Cs – Color, Clarity, Cut, and Carat Weight – along with a plotted diagram of its clarity characteristics and a graphic representation of ...

Use the form below to submit a request to list your location on the GIA Retailer Lookup. Have multiple locations? Use the multi-store tool to make registration easier. Click here to update your store ...

Fine amethysts have been set in religious jewelry and royal crown jewels for ages. It was once considered equal in value to ruby, emerald, and sapphire.

这颗克什米尔蓝宝石拥有强烈的天鹅绒般蓝色。——摄影：Robert Weldon（罗伯特·韦尔登）/GIA。 蓝宝石是有色宝石三巨头之一，另外两种是红宝石和祖母绿。人们把这种坚固的宝石定为 九月生日石，它以实用性和浪漫气息吸引了众多珠宝买家。 红宝石和蓝宝石均属于刚玉矿物。红色的刚玉称为红 ...