About GIA

A Tradition Of Science and Education

Established in 1931, GIA is the world’s foremost authority on diamonds, colored stones, and pearls. A public benefit, nonprofit institute, GIA is the leading source of knowledge, standards, and education in gems and jewelry.

Welcome to GIA.

EDUCATE

Students around the globe turn to GIA for the knowledge, skills, and credentials that launch successful gem and jewelry careers.

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RESEARCH

The world leader in gemological research, GIA’s breakthrough discoveries deepen our understanding of gemstones and the world.

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PROTECT

Through research, education, and unbiased gem grading and analysis, GIA strives to protect the gem and jewelry buying public by setting global quality standards.

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CREATOR OF THE 4Cs

In the 1940s, GIA established the “4Cs” and the International Diamond Grading System? – to this day, the worldwide standard for evaluating diamond quality.

Cut

diamond cut

The sparkle and brilliance of a diamond depends more on its cut than anything else.

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Clarity

diamond clarity

The absence of inclusions and blemishes makes a diamond rare and affects value.

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COLOR

diamond color

Diamonds in the D-to-Z color range are valued by how closely they approach colorlessness – the less color, the higher their value.

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CARAT WEIGHT

diamond carat weight

Diamonds and gemstones are weighed in metric carats: one carat is equal to 0.2 grams, about the weight of a paperclip.

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