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Diamond Certification

We believe your jewelry purchase should be one of joy. You should feel confident you're getting what you pay for

We believe that grading authorities should stand behind their work. That all diamonds can be, and should be, graded accurately and consistently

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国产成 人 综合 亚洲

Get the knowledge to ask the right questions. To feel confident in yourself. Confident in what you give. To make sure that you're getting the best diamond for your money.
Learn about the 4C's

The 4Cs are the foundation of assessing diamond quality. Learn what they mean so you can find the perfect diamond.

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Why you need a GCAL certificate

Before investing in a diamond, know who's rating the quality. Each grade difference means big money. Be sure your diamond is accurately graded.

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HOW THE 4C'S AFFECT PRICE

Bigger or higher quality? See how each diamond grading factor affects price so you can make the right decision within your budget.

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When you need gemological expertise, rely on GCAL's team of
highly trained gemologists, for accurate and unbiased analysis.

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GCAL LAB TOUR VIDEO

DIRECT ASSESSMENT IMAGING
  • symmetry & brilliance

    The most true-to-life method to assess CUT quality is by Direct Assessment technology

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  • HEARTS & ARROWS
    HEARTS & ARROWS

    Precision cutting produces symmetrical patterning that is captured in hi-res photos

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  • 360 VIDEO

    Stunning videos record the sparkle and beauty of your diamonds and gemstones

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  • IMAGING

    Hi-res photographs of the crown and pavilion record a diamond's true beauty

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WHAT THEY'RE SAYING