WHY GCAL? Glad you asked. Here are some of our Exclusives and Testimonials.
One Location • One Standard • Graded in the USA


We believe experts should stand behind their work, that's why we issue Grading Certificates, not just grading reports. Our certificates come with a money-back guarantee so you can feel good knowing you got exactly what you paid for.

The fine print
Have you ever looked closely at a diamond report from one of the leading laboratories? It is riddled with small-print disclaimers refusing any liability for errors in judgment. That's right. If the D-color diamond you bought turns out to be E or F or lower, you're out of luck. Courts have frequently ruled that sellers, not labs, are responsible for such errors. Why? Because the labs warned you beforehand on their reports that they couldn't be held responsible.

GCAL thinks buyer-beware diamond reports are irresponsible and unethical. Indeed, GCAL thinks such documents should be called "reports" instead of "certificates." Why? Because true certificates carry liability on the part of the lab that issued them. That's why GCAL became the world's first- and still the only- gem lab to guarantee its color and clarity grades in writing. When introduced in 2000, this money-back grading accuracy guarantee elevated the GCAL diamond document from report to certificate.

GCAL Guaranteed Diamond Grading Certificate
The 4Cs Grading Consumer Guarantee ("Guarantee") is fundamental to GCAL's concept of independent, third-party grading. This Guarantee ensures that the carat weight and the quality grades (cut, color and clarity) in a GCAL by Sarine 4Cs Grading Certificate (“4Cs Certificate”) are accurate within recognized gemological tolerances, subject to the limitations below. GCAL also guarantees that the diamond certified in a 4Cs Certificate is an authentic natural or lab-grown diamond.

The Guarantee is valid for a period of two years from the date on the applicable certificate. The Guarantee does not apply to a diamond that has been subjected to damage, treatment, re-polishing, re-cutting or other alterations, or to a diamond with evidence of alterations of any kind as determined by GCAL. The Guarantee is not transferable and is void if the diamond was acquired illegally or used in the commission of a crime, or used in violation of applicable laws and regulations. The Guarantee is only applicable to a consumer who purchased the diamond for legitimate personal, family or household purposes.

If you have reason to believe that the carat weight or any of the cut, color or clarity grades provided in your 4Cs Certificate is lower than the weight or quality grade of your certified diamond, you may, within two years of the date on the applicable 4Cs Certificate, submit your diamond for a guarantee challenge. If GCAL determines that either the weight or quality grade is lower than the weight or quality grade originally assigned on the applicable 4Cs Certificate, or that the diamond was incorrectly authenticated, GCAL will reimburse you for the difference between what you paid for your diamond and the current fair market value of an equivalent diamond in the market in which it was purchased, pursuant to the current established grades or weight as may be applicable. The current fair market value will be solely determined by GCAL.

Contact GCAL offices prior to sending your diamond for review. There will be a consumer guarantee challenge submission fee and return shipping charge quoted at time of notification. Your diamond must be unmounted and accompanied by a copy of the original retail sales receipt and the original 4Cs Certificate, without exception.

GCAL Gemologists Diamond Grading Experts Our Guarantee

GIA Diamond Grading Report
This report is not a guarantee, valuation or appraisal and contains only the characteristics of the diamond described herein after it has been graded, tested, examined and analyzed by the GIA Laboratory and/or has been inscribed using the techniques and equipment used by the GIA Laboratory at the time of the examination and/or inscription. ... GIA and its employees and agents shall not be liable for any loss, damage or expense resulting from any error in or omission from this report or from the issuance or use of this report or any inscription, even if the loss, damage or expense was caused by GIA or any of its employees or agents.

GCAL Gemologists Diamond Grading Experts Jewelers Loupe Our Guarantee

AGS Diamond Quality Document
This Diamond Quality Document is not a guarantee, valuation or appraisal, and American Gem Society Laboratories, LLC has made no representation or warranty regarding this document or the value of the diamond herein ... AGS Labs and its employees and agents shall not be liable for any loss, damage, or expense for any error in or omission from this document or for its issuance or use even if caused by or resulting from the negligence or other fault (except fraud, willful misconduct or gross negligence) of AGS Labs or its employees or agents, and shall not be liable for special or consequential damages for any error or omission caused by the acts of others...

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