Certificate checker
Verify a lab-grown diamond grading report
Enter the report number to open the laboratory's own report check. Then compare the details with the stone in your hand.
What to compare
- Report number and laser inscription. Most graded stones carry the report number inscribed on the girdle. Check it with a 10× loupe or microscope.
- Measurements and carat weight. They should match the stone to the hundredth of a millimetre and carat.
- Shape and cutting style. The outline and facet arrangement should match the report's diagram.
- Growth method. The report states CVD or HPHT.
- Treatment. The report notes any post-growth treatment.
If anything does not match, contact us before setting the stone.
Questions buyers ask
How do I check a grading report?
Use our certificate checker, which opens the laboratory's own report-check page for the number you enter. Compare the measurements, carat weight and laser inscription with the stone you receive.
Do you disclose post-growth treatment?
Yes. Some CVD diamonds are treated after growth to improve colour. We tell you which stones are as-grown and which are treated, and independent grading reports note it.