WHY GCAL? Glad you asked. Here are some of our Exclusives and Testimonials.


We believe in doing things the right way, not the easy way, that's why we don't cut corners. With only one location in the USA, we have complete control of maintaining high standards, training and consistency.

Diamonds should be graded accurately
Sounds simple right? Yet so many diamonds are ‘over-graded’ or ‘mis-graded’. Unfortunately greed motivates the all too common industry practice of inflating quality grades. Consumers are presented with diamonds of supposedly the same grades that are actually vastly different. This means, for example, that an H/SI1 diamond could actually be J/SI2 worth far less.

At GCAL, we understand the importance of your diamond. We know consumers rely on our grading to make significant financial decisions. We take that responsibility seriously.

We don't cut corners
Our corporate culture is characterized by our commitment to accuracy. We examine every diamond as if it were for a friend – precisely measuring, analyzing, photographing, Gemprinting, and thoroughly grading it to the highest standards. No matter the size - from 0.20 carat to over 50 carats, the origin - natural or lab grown, or the quality - flawless or included, every diamond is given the same attention.

Daily Calibration
We are committed to maintaining meticulous standards. Our instruments are verified and calibrated daily, our expert staff is highly trained and our standards are well documented. We believe challenging ourselves leads to better performance, that's why our methods and procedures are independently audited annually, ensuring we uphold the standards of the ISO 17025 Laboratory Accreditation.

GCAL is one of only three diamond grading labs in the world that is ISO 17025 Accredited. In 2014, we were proud to become the only gem lab in the world to earn the prestigious ISO 17025 Forensic Accreditation. Read more about Our ISO 17025 Accreditation

One location, one standard. Graded in the USA
Locations in Antwerp, Mumbai, Dubai? Nope. This is by choice. All analysis and certification is performed in one lab in the USA. We have complete control of our standards, training and consistency.

GCAL Gemologists Diamond Grading Microscope Our Standards

The bottom line
Not all grading labs are created equal. Some are not quite as independent, honest or as experienced as others. Make sure your diamond is graded by a reputable laboratory because you don't want to find out that the H/SI1 diamond you just paid for is actually a J/SI2 worth far less. Read the fine print on the grading report that comes with your diamond. Remember - GCAL is the only diamond laboratory to stand behind their grading certificates with a money-backed consumer guarantee. Read more about Diamond Certification

GCAL Gemologists Diamond Grading Experts Our Standards

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