Grading and reports
A practical guide to diamond grading reports
A grading report describes a diamond’s characteristics. Use it as one part of due diligence, alongside supplier checks and inspection of the stone.
Read the individual fields
Review shape, measurements, carat weight, color, clarity and finish. Check comments, plotted characteristics and disclosures about treatments or growth.
Check the report at its source
Where available, use the issuing laboratory’s report-check service. Match the report number and specifications to the offered stone.
Separate grading from commercial value
A grading report is not a supplier guarantee or transaction agreement. Price, currency, taxes, payment, inspection and returns must be confirmed directly.
Editorial review
Reviewed by Only Carat editorial team. Updated 2026-10-23.