Products and Services

GSL offers a comprehensive range of diamond grading and jewelry appraisal services to the jewelry trade and public consumer:

Diamond Certification:

Pre-Cert™

Diamond grading, printed on a convenient parcel-sized sticker. Each diamond is assigned a unique GSL identification number. Includes measurements, carat weight, clarity, color, cut, polish and symmetry.

Detailed Diamond Grading Report

Diamond grading, as well as more comprehensive proportion measurements and detailed profile image. Each diamond is assigned a unique GSL identification number. This report can be issued with a Replacement Value, upon request.

Diamond Grading Sealed CertiCard®

Diamond grading, printed on a specially designed sealed certificate card, which secures the diamond with its certification. The sealed card’s security packaging seals must be broken in order to remove diamond. An ideal way of ensuring the diamond is presented with its certification. Includes measurements, carat weight, clarity, color, cut, and comprehensive proportion measurements (on reverse).

Available upon request:

  • Diamond Plotting

    A representative image of your diamond which shows the inclusions within the diamond

  • Firetrace

    FireTrace predicts the light reflecting properties of a diamond, with three properties meaured: brilliance, dispersion, and scintillation

  • Fluorescence Check

    Indication of level of fluorescene when diamond is viewed under long-wave ultraviolet light. For identification purposes.

  • Polish & Symmetry

    Assessment of smoothness of surface of diamond and facet arrangement

Online Services:

Report Check

Online Report Check allows certificate holders to verify/look up details of a particular certificate.