Diamond Grading
The Value Standards of Diamonds

Like any other quality of valuable product diamonds have standards. Diamond grading or Certification is the industry standard for quality assurance.

The Certification provides a complete evaluation of quality and genuineness of your loose diamonds. A complete analysis of your diamond by a team of professionals, will give you accurate information of its Cut, Color, Clarity and Carat (stone weight).

About the GIA

This Certification is issued by the Gemological Institute of America (GIA), which is one of the most respected laboratories in the international diamond industry.

The GIA was formed in 1931 and is a non-profit organisation. They do not buy or sell diamonds. They are an educational and research institute.

Please be aware that the loose diamonds graded by a person who graduated from GIA is not the same as a GIA graded diamond.

A Cautionary Note...

I recommend that you do not purchase a loose diamond from anyone who grades and sells at the same time because it easy to over-grade the stone as there is a conflict of interest (making a profit versus giving an honest grade).

GIA operates like a neutral mediator between the buyers and sellers, hence it is internationally trusted for diamond grading.

The first thing that the reputable graders do when executing the diamond ratings, is to differentiate diamonds from fakes. In doing so they use the Scratch Pen which is a very simple tool developed for the identification of diamonds.

This pen will scratch any surface except for diamonds. A diamond is the hardest mineral found on earth and only a diamond can be used to scratch or cut another diamond. If this test holds true then they proceed with diamond ratings on the 4 C's.

Cut

The Grader uses newly developed computer or profile projector to analyse and measure the proportions of a loose diamonds for rating purposes.

The crown height, pavilion depth and table width can thus be measured precisely as a percentages of the diameter of the loose diamond.

Color

All reputable graders possess a Master Set containing the entire range of White Stones. The color ratings of a loose diamond are determined by visual comparison of diamonds against the white master board stones.

Clarity

The Daylight lamp is a critical piece of equipment for graders when rating the stones as they must see any inclusions (imperfections) and flaws. Therefore, appropriate illumination is very important when examining the clarity ratings of a polished loose diamonds.

Carat (Stone Weight)

The weight of a diamonds is expressed in carats. The typical scales are used to determine the carat weight of a diamond.

Carat weight of a loose diamond is one of the most important factors in determining the market value of a gemstone. Profit loss would definitely occur if the incorrect stone weight is recorded. Therefore, extremely precise evaluation is necessary.

Microscopes

Microscopes are used for the most accurate clarity diamond ratings of a loose diamond. They further use Tweezers to hold a diamond during the evaluation of its clarity.

If graders use fingers to hold a diamond, the stone will get dirty and again fingers will conceal a large portion of facets. Therefore, this will affect the clarity rating.

Tweezers

There are two ways of holding the stone with a tweezers which are as follows:

• Girdle Hold - the table of the stone is placed upon a soft surface, and the tweezers grasp the stone at its girdle. This hold allows for a thorough examination of the crown (top) and the pavilion (bottom).
• Culet/Table Hold - The tweezers grasp the stone with one arm covering the table and the other culet. The girdle protrudes outside the tweezers arms and the stone can be rotated along an axis formed by the culet and the centre of the table.

  After the grader has examined all internal and external characteristics of a stone then they record diamond grading information of the 4 C's in a Diamond Grading Report (called Certificate).

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