Certification Education
The Science Behind Every Grade
GCAL 8X is not a marketing label. It is the only diamond certification backed by eight measurable optical parameters and a zero-tolerance grade guarantee.
Every stone begins here. GCAL 8X is where it ends.
Gem Certification & Assurance Lab
"The only certification lab in the world that guarantees its own grades."
Founded in the United States, GCAL is an independent, ISO 17025 accredited forensic laboratory specialising in diamond grading and gemstone identification. Direct evidence accompanies every grade it assigns.
ISO 17025 Accredited
An independent forensic laboratory meeting the most rigorous scientific accuracy standards in the industry.
Photographic Proof
High-resolution photographs of the actual diamond — not illustrations — included on every certificate.
Zero-Tolerance Guarantee
The only lab globally that backs its grades with a financial guarantee. If a grade is wrong, GCAL pays.
Laser Inscription
Certificate number laser-inscribed on the girdle — permanent traceability for the life of the stone.
The Standard
Eight Parameters.
Zero Exceptions.
A diamond earns GCAL 8X only when every single parameter achieves the highest grade simultaneously.
From GCAL
Why GCAL Created
the 8X Cut Grade
Why It Matters
Why GCAL Matters
ISO Accredited
Forensic laboratory methodology — the same accreditation used by scientific testing institutions worldwide. Every grade is backed by direct, measurable evidence.
Photographic Proof
Your diamond's actual photographs appear on its certificate. No stock images, no renderings — only the stone itself, captured in full resolution.
Guaranteed Grades
GCAL is the only laboratory that backs its grades with a financial assurance. A grade is not an opinion — it is a guarantee.
Laser Inscription
The certificate number is laser-inscribed on the girdle, permanently linking stone to report. Traceability that lasts a lifetime.
GCAL Certified
Shapes We Certify
Every shape available from Maruti Export passes all eight GCAL 8X optical parameters — without exception.
World's Largest
GCAL 8X Diamond Manufacturer
Every GCAL 8X diamond from Maruti Export is backed by photographic proof and a guaranteed grade — vertically manufactured in Surat, India to the most rigorous cut, polish, symmetry, and light performance standards in the world.
GCAL 8X FAQ
GCAL 8X Questions, Answered
What does GCAL stand for?
GCAL stands for Gem Certification & Assurance Lab, an ISO 17025 accredited independent gemological laboratory known for forensic-grade diamond grading, photographic proof on every certificate and a financial guarantee on its grades.
What are the eight parameters of GCAL 8X?
The eight GCAL 8X parameters are cut grade, polish, symmetry, light performance, proportions, finish, optical symmetry (Hearts & Arrows) and 8X excellence, which requires all of the other parameters to achieve the highest grade at the same time.
Is GCAL 8X better than a standard Excellent cut grade?
GCAL 8X is stricter than a standard Excellent cut grade. Every one of the eight parameters must achieve the top grade simultaneously, with no partial credit, and the result is backed by measured light-performance data and photographs of the actual stone.
How can I verify a GCAL 8X certificate?
Every GCAL certificate number is laser-inscribed on the diamond's girdle, permanently linking the stone to its report. The certificate also carries high-resolution photographs of the actual diamond, so the stone and report can be matched visually.
Who manufactures GCAL 8X lab grown diamonds?
Maruti Export of Surat, India, is the world's largest manufacturer of GCAL 8X certified lab grown diamonds, supplying them in every shape and size to the global jewellery trade.