How to Tell If a Diamond Is Real: Check the Paperwork

In this guide

    By Clint Casmiro, Co-Founder, Smiro Studio · Updated October 22, 2026

    Short answer: Check the paperwork, not a trick at home. Every diamond we sell at 1 carat and up has an IGI report, and the report number is laser inscribed on the stone's girdle, so a jeweller can match the two and you can look the number up on IGI's website. A lab grown diamond is a real diamond and passes a diamond tester; only lab equipment tells lab grown from natural.

    A loose 3.03 carat cushion champagne diamond resting on a hand

    What is the most reliable check?

    A grading report you can match to the stone. The report number is inscribed on the girdle, the thin edge around the diamond, and a jeweller with a loupe can read it and check it against the paper. Then enter the number on the lab's website. How to read an IGI report is in IGI certified lab grown diamonds.

    Is a lab grown diamond real?

    Yes. It is carbon in the same crystal as a mined diamond, 10 on the Mohs hardness scale, and it passes a diamond tester. Only specialist lab equipment can tell lab grown from natural, which is why the report states the origin. See lab grown vs natural diamonds.

    Can a diamond tester be fooled?

    Sometimes. As general gem knowledge, some basic handheld testers can read moissanite as a diamond, so a tester alone is not proof. A report matched to the stone is. More in lab grown diamond vs moissanite.

    Do home tests work?

    Not for the questions that matter. A home test cannot tell a lab grown diamond from a natural one, and it cannot give you a grade. Use the report, or ask a jeweller to check the inscription.

    What if I want an independent opinion?

    Get an appraisal. For $100 CAD we arrange a certified appraisal from a third party gemologist, an independent valuation you can also give your insurer. See appraisal and insurance.

    How do I know the stone I paid for is the one in my ring?

    See it before you commit. We send you two stones, each with a 360 video and its IGI certificate, and the one you pick is the one we set. Then a close-up video of the finished ring comes before you pay the balance.

    Want us to look at a stone with you?

    A free 20 minute video call with our team. Bring a photo, a budget, or nothing at all.

    Book a free callGet a free estimate

    From our collection

    3.02ct cushion champagne diamond3.02ct Cushion Champagne Diamond3.16ct Marquise Champagne Diamond3.16ct Marquise Champagne DiamondPair of 2ct Old European Champagne DiamondsPair of 2ct Old European Champagne Diamonds1.24ct rose octagonal champagne diamond on the hand1.24ct Rose Octagonal Champagne Diamond

    Questions we get about this

    How can I tell if my diamond is real?

    Match its grading report to the number laser inscribed on the girdle, then look the number up on the lab's website.

    Do lab grown diamonds pass a diamond tester?

    Yes. A lab grown diamond is a real diamond and passes a diamond tester.

    Can moissanite pass a diamond tester?

    Some basic handheld testers can read moissanite as a diamond, so a tester alone is not proof.

    Can a jeweller tell if a diamond is lab grown?

    Not by eye. It takes specialist lab equipment, which is why the report states the origin.

    Keep reading

    Written by Clint Casmiro, co-founder of Smiro Studio with Karina. We are second generation jewellers. Our dad Kenny has more than 40 years at the bench and oversees production, and we have built over a thousand tulip basket rings. Every ring is designed in CAD and you approve 3D renderings before production. We ship free and insured across Canada and the US.

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