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


  • "Dear GCAL...we work with almost all major labs. None of which come close to the professionalism and courtesy, shown towards us the way only GCAL can." -Diamond Manufacturer, NY, NY

  • "Your certificates are always accurate and that's why I use them. I value them equally with GIA." -Jeweler, Buffalo, NY

  • "It has been a great partnership with GCAL, and everyone in the team goes above and beyond their role to help us meet our business objectives." -Online Retailer, Seattle, WA

  • "You are the best in support and product. Gemprint is the best thing we have ever done." -Jeweler, Troy, MI

  • "You guys are the best around. Once we point out your guarantee against what the bigger labs do, there are no more questions about your lab, you put your money where they can see it in writing. Please keep up the good work, you will continue to get our business." -Jeweler, Long Beach, CA

  • "Excellent all around. A great resource for more than just grading stones. A+++++" -Insurance Adjuster, Worcester, MA

  • "All our employees love using the GCAL report when showing diamonds to our customers." -Jeweler, Waterville, ME

  • "Angelo and Don have been an absolute pleasure and have gone out of their way to help us combat issues of potential counterfeit jewelry being sold." -Online Retailer, San Jose, CA

  • "It is a pleasure to do business with GCAL. The most professional and accurate lab I have worked with in my 30 years of being in the industry." -Professional Jewelry Appraiser & Educator, Portland, OR

  • "Great company to deal with. Honest ,fair, and customer service is the best of any lab." -Diamond Manufacturer, NY, NY

  • "Appreciate Mr. Palmieri's monthly overview of the state of the global diamond community." -Jeweler, Johnstown, PA

  • "The services of GCAL are exceptional. Their verification process should be an industry standard. This is an essential consumer protection program." -Jeweler, Phoenix, AZ

  • "Fantastic organization with wonderful ethical culture" -Jeweler, New York, NY

  • "GCAL is open, transparent and very easy to work with, they really stand out against other laboratories." -Manufacturer, Lafayette, LA

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