Clarity is a term used for describing the number and size of inclusions in a diamond. Inclusions are mainly traces of non-crystallized carbon that may appear on the diamonds internally or externally. A flawless diamond contains no inclusion and is considered extremely rare and valuable. Large inclusions affect the brilliance of the stone as they interfere with the dispersion of light.

We grade diamonds on the basis of purity by determining following categories:

Diamonds close to being colorless are more rare and valuable. Diamonds that display little color allow more light to pass through, resulting in a burst of brilliance. On the basis of color, diamonds are allocated a grade, starting with D grade (for colorless diamonds) and ending in a Z+ grade. Some diamonds are also found in vivid colors such as red, blue and pink.

Cut gives a unique sparkle and brilliance to diamonds. Cut quality depends on the craftsmanship of the diamond cutter. If a diamond has perfect color and clarity but the cut is poor, it will lose its brilliance.

We grade diamonds on the basis of cut by determining following categories:

Polish mainly describes the smoothness of the facets in a diamond. This is the last step in the diamond cutting procedure. Brilliance of a diamond can be enhanced with a smooth polishing of the facets.

Diamonds are graded on the basis of polish by determining following categories:

Symmetry refers to the alignment of the facets (surface conditions) in a diamond. Each facet needs to be of a consistent size and positioned opposite the corresponding facet. Poor symmetry misdirects the light that enters the diamond.

Diamonds are graded on the basis of polish by determining following categories:

An impeccable round diamond with perfect angles is called ‘Heart and Arrows’ (H&A). These diamonds are graded with extra specifications under SGS. They are not included in the regular cut criteria as H&A diamonds are considered better than the most excellent cut diamonds.

Luster and brilliance are two most valued attributes of a diamond. Luster describes a diamond’s fire and sparkle. Milkiness is mainly a hazy inclusion in the diamond that appears white or grey in color. This haziness affects the brilliance of a diamond. Depending upon the light reflected from the stone, SGS grades diamonds on the basis of three levels of luster, and three levels of milkiness:

Level of Brilliance:

When exposed to ultraviolet radiations, a diamond glows if it carries the characteristic of fluorescence. Black light is the most common source of UV exposure in which many diamonds give off a glowing blue coloration.

SGS grades diamonds based on the level of fluorescence present in them:

As compared to the total inclusions, we grade diamonds on the basis of black inclusions by determining the following categories:

We grade diamonds on the basis of black inclusions as compared to the total inclusions by determining the following categories:

Open inclusion is a small, shallow opening on the surface of a diamond, often found near the girdle, culet or facet junctions.

grades diamonds with open inclusions as mentioned below:

It is an extra facet that is placed on a diamond’s normal facet without considering the symmetry of the stone. These are additional to the facets required for making a brilliant cut diamond.