Established in 1931, the Gemological Institute of America (GIA) is the world’s foremost authority on diamonds, colored stones, and pearls. A public benefit, nonprofit institute, GIA is the leading ...

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 ...

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, ...

To convert your current GIA report to a different report type, submit the gemstone along with its original GIA report and note that you would like Report Conversion service on your Service Order ...

Large quantities of rubies—both rough and faceted—from a commercially important new source in Myanmar (Burma) have been available on the Bangkok market since 1992. The ruby crystals from the Mong Hsu ...

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.

Tairus, in Novosibirsk, has produced yet another new type of Russian hydrothermal synthetic emerald, now being marketed in Bangkok. Examination of eight faceted samples revealed that, with the ...

Observations of Oval-, Pear-, and Marquise-Shaped Diamonds: Implications for Fancy Cut Grading Presents findings from observations of oval-, pear-, and marquise-shaped diamonds, laying the groundwork ...

标记每个晶体边缘的切口被称为重入角。 宝石爱好者通常将其形容为“白天的祖母绿，晚上的红宝石”，亚历山大变石是金绿玉矿物中非常罕见的变色类别。 它最初在 19 世纪 30 年代被发现于俄罗斯的乌拉尔山脉，现在，斯里兰 卡、东非和巴西都发现了它的 ...

Upon receipt, each item is immediately weighed and measured and assigned a control number that will follow your stone through a meticulously detailed tracking process that ensures the item submitted ...

Federal student aid programs generally cover 40–50% of tuition. Many GIA on-campus students borrow additional funds through either the Parent Loan Program (PLUS) if they are dependents, or through ...

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.