What makes CGL unique and distinguishes it from other labs is the very high and precise level of inspection and description of diamonds, gemstones or jewelry. Not every lab is authorized or is skilled enough to grade diamonds to the highest possible level.

At CGL, we believe that clients must know the precise characteristics of the stones in their possession, particularly because we are talking about items that are expensive and – in many cases – extremely costly.

This is the case whether the stone is bought for investment, for personal use, or in a jewelry item.

Not everyone can grade a diamond: the stone must be inspected and checked by an expert authorized to do so according to the highest standards and the most modern equipment available in the industry. And at CGL, our grading experts use the most sophisticated machinery and devices on the market for the inspection of diamonds and gemstones.

Our streamlined and efficient work processes enable us to inspect and grade stones at the highest levels of precision.

Reports are provided for all kinds, sizes and shapes of natural, transparent and colored diamonds as well as gemstones and jewelry.

The aim of a diamond certificate is to provide the highest level of grading possible for a diamond or gemstone. The report gives a precise description of the stone's characteristics according to the 4cs – Carat, Clarity, Cut, and Color.

The results of all CGL certificates are kept on file by CGL, and for your convenience we enable you to retrieve them online.

We offer a range of certificates aimed at providing the services required by our wide range of customers.
These include:

Full Diamond Grading Reports
These reports include an assessment of the 4Cs of the diamond, measurements and other important parameters of the diamond, together with a high resolution picture of the diamond and a graphic image of its proportions. A diagram of its specific clarity is optional.

Jewelry Identification Reports
We provide independent and expert information on the jewelry item, and the precious stones set in it, with total carat weight, color, clarity, and details of mounting, as well as a high resolution picture of the jewelry. We give clear documentation to enable the owner to see exactly what the jewelry contains.

Jewelry Appraisal Reports
A detailed report on the jewelry item, containing all the parameters given in the identification reports, as well as a value appraisal according to our opinion of the market price, and a high resolution picture of the jewelry item.This report gives a completely objective evaluation and identification by our skilled and experienced graders.

Full Gemstone Grading Reports
A comprehensive examination giving all the details of the gemstone, including total carat weight, measurements, color, etc. A high resolution picture of the gemstone is included.

Fancy Color Diamond Reports
This report gives shape and cut, carat weight, and measurement, along with color description. A high resolution picture is included.

Mini Certificates
This compact certificate provides the 4Cs of the stone, and its proportions, meaning dimensions, total depth, table width and girdle. In addition, there is an evaluation of the finish of the stone – its polish and symmetry. There is also a high resolution picture of the diamond.

Sealing Service
We offer our customers with total solutions, and to provide complete reassurance, we offer a diamond-sealing service. This is a fail-safe way of ensuring that a diamond and its certificate go together and prevent any possibility of a mix-up. Sealing also prevents the diamond from coming into contact with grease and dirt, allowing you to offer it for sale to a potential client in perfect condition.

Preliminary Examination
Diamantaires often require a brief examination to ensure that they are in line with their requirements before ordering a full certificate. We have created a preliminary examination service to give our clients maximum flexibility. This service grades basics of the diamond – weight, cut, color and clarity. The results of the grading are printed on labeled parcel papers and stored in our database.