The Gem Testing & Certification Laboratory of India (GTCL) was established with a singular mission: to provide accurate, unbiased, and internationally recognised gemological certification to every gemstone buyer and seller in India.
We operate at the intersection of ancient gemological wisdom and modern scientific technology. Our team of certified gemologists uses advanced spectroscopic equipment, microscopy, and refractive index measurement to provide the most accurate assessments possible.
Whether you are a wholesale dealer, retail jeweller, astrological consultant, or first-time gemstone buyer — our certificate gives you complete confidence in every stone.
Every gemstone is tested using internationally standardised methods with precision instruments.
We maintain complete independence — no buying, selling, or trading of gemstones.
Our lab is equipped with spectrometers, polariscopes, refractometers, and microscopy systems.
Our certificates clearly document all findings with no ambiguity or hidden results.
Standard turnaround within 3–5 working days, with express service available.
Services available across India via courier, walk-in, and partnership channels.
Send your gemstone via insured courier or visit our lab in person.
Our gemologists perform physical, optical, and spectroscopic analysis.
A detailed certificate is generated with QR verification.
Certificate and gemstone returned via secure insured courier.
