About SNJ Grading System (SGS)

We educate our customers about our minute grading system on various factors. Due to this we can take full advantage to promote & increase our business through E-Commerce. We manufacture 0.30 cts to 10 cts sizes in Round, Princess, Marquise, Pear, Oval, Square Emerald, Emerald, Square Radiant, Radiant, Heart, Cushion etc. Grading is carried out according to rigorous criteria mapping with Labs of International repute & various other minute factors developed by our well Equipped Research Laboratory Team. In our laboratory we have taken care of each C's in depth so that you can visualize the stone in front of your eyes. Our grading is based on GIA system so there is higher chance of upward color certification in other Lab. To narrow down the price band we give (+) color & (+/-) clarity grading.

Carat

The unit of measurement used to describe the weight of diamonds is called 'Carat'. The 'Carat' weight is commonly expressed in points or fractions.

1 carat is equal to 0.2 grams, or 0.007 ounces.

5 carats is equal to 1 gram.

141.7 carats is equal to 1 ounce.

There are 100 points in 1 carat. For instance, 0.33 carats is generally expressed as 33 points, or 1/3 of a carat.

Carat means weight of diamond which reflects its size. One carat diamond weighs 100 cents. (1 ct = 100 cents ) Diamond sizes can be expressed by its weight (unit), pointers or stones per carat.

Color Scale

Diamonds act as prisms, dividing light into a spectrum of colors and reflecting this light as colorful flashes referred to as a diamond's 'fire'. The more colorless a diamond is, the more vividly colorful the 'fire' will appear.

Diamonds come in every color of the spectrum, but the most popular gems are colorless. Truly colorless, icy-white diamonds are extremely rare, and therefore, most costly. Stones are graded by color and given designations dependent on how far they deviate from the purist white.

The best way to see the true color of a diamond is by looking at it against a white surface. Although the majority of diamonds come in shades of white, the gems also come in a spectrum of majestic colors, from red and canary yellow to blue, green and brown. These colorful diamonds, known as fancies, are valued for their depth of color, just as white diamonds are valued for their lack of color.

Grades in the color of diamonds range from D - Z. D is being truly colorless and of the highest quality. E and F are also graded as colorless while G, H, I and J are near colorless. Diamonds graded K, L and M will have obvious hints of color and as the scale approaches P, you may find subtle changes in hue and tone. The exceptions to the rule are 'Fancy' diamonds in well-highlighted colors that include pink, blue, red, green and canary yellow. These are particularly rare and highly treasured.

Clarity Grade

A diamond's clarity refers to the presence of identifying characteristics on and within the stone. While most of these characteristics are inherent qualities of the rough diamond, and have been present since the earliest stages of the crystal's growth below ground, a few are actually a result of the harsh stress that a diamond undergoes during the cutting process itself.

CUT (PROP)

Diamond's beauty depends upon optical properties such as high Refractive index, color dispersion, luster & high degree of clarity. We give strong thrust on cut grading. Due to well equipped manufacturing system our stones are best polished. Luster means fire of diamonds. Better the Polish, brighter & more lustrous the stone. At the time of cutting take care that the light entering from top should not be lost through the teak pavilion sides. So Customer gets to observe almost 100% light from a round brilliant cut diamond. i.e. (82-83% from total internal reflection & 17 -18 % from luster). This phenomenon is known as "LIFE". As diamond critical angle is 24*, brilliance of diamond depends upon pavilion facets & pavilion angle. Cut determines brilliance. In RBC diamond Crown facets act like small prism, which split white light. Small crown gives less Dispersion & more Brilliance vice versa.

Lay people often confuse a diamond's SHAPE with its CUT; this is most likely due to the industry's synonymous use of the terms "cut" and "shape" to describe a diamonds shape (outline), i.e. marquise cut, round brilliant cut, or pear shape. In reality when we refer to the "cut" or "make" of a diamond, we are really referring to a compilation of three factors. It’s PROPORTIONS in terms of degrees and percentages... the quality of its POLISH or finish... and the SYMMETRY of its facets... These three factors result in the "Overall Cut Grade" of the diamond.

POLISH - PO

Polish can be result of the finishing process or be affected by blemishes created after cutting. The term "Polish" refers to the degree of "polishing lines" that appear on the surface of a finished diamond which can be seen with the use of 10x magnification. These polishing lines are caused by the minute diamond crystals which are embedded in the polishing wheels used by the diamond cutters to polish the surface of the diamond after cutting. While not quite the same in appearance, they are similar in concept to the swirl marks left on the surface of a car from the use of an orbital buffer, but are much less noticeable. It is important to note, however, that polish lines are straight in appearance.

SYMMETRY - SY

Symmetry refers to the precision with which the facets of a diamond are aligned with each other and the consistency of facet shape and size per given section. The symmetry rating reflected on a diamond grading report is not an indication of the proportions of a diamond.

HEARTS & ARROWS (HA)

Faceted diamond forms a well aligned, symmetrical & balanced form that reveals the well known eight rayed arrow pattern which you can see through special device like the Fire scope by keeping diamond face up. Here symmetry pattern can be seen in perfect order. Perfect Heart shape will be observed from the pavilion side. Maximum Life, Fire, & Sparkle are observed in diamonds that has been cut, faceted in certain specific proportions. These parameters are followed by our skilled artisans.

FLUORESCENCE – FL

When we speak of Diamond Fluorescence, we are referring to the diamonds tendency to emit a soft colored glow when subjected to ultraviolet light (such as a "black light"). Fluorescence is a form of illumination that is created when a diamond is exposed to low or high wave ultraviolet radiation. Faint or medium fluorescence will rarely affect a diamond's appearance. Usually fluorescence is unnoticed by the human eye in ordinary light. Fluorescence can cause a diamond to appear less clear or slightly hazy if the diamond exhibits very strong or extreme fluorescence. When selecting your diamond it is best to choose a diamond that has no fluorescence or faint to moderate fluorescence.

LUSTER - LU

This is another parameter, which has been found of importance in determining the exact purity of the diamond. The amount of light that the stone reflects and the type of light that is emitted by the stone determine luster of a diamond. Luster refers to the quality of a surface in reflected light. The luster of a diamond is usually described as adamantine luster.

GIRDLE

The outer edge of a diamond which forms a band around the stone. The girdle can be faceted or non-faceted

CULET

A diamond's culet is the point on the bottom of a diamond's pavilion. A diamond's culet may be pointed or it may be blunted with a small facet. The culet facet can vary in size. This culet's size determines the grade that the culet is assigned.

EXTRA FACETS - EF

Occasionally a cutter will find the need to remove an inclusion near the surface or to compensate for facets which do not meet correctly and he will add an "extra facet". Extra facets have no effect on clarity grades. This is subdivided in Two parts: - 1) EFCR: - Extra Facets on Crown, 2) EFPV: - Extra Facets on Pavilion.