Grading

Performance in grading and standardizing diamond evaluation is a much sought after quality by diamond laboratories worldwide.
However, grading specifics within the trade are mostly far more accurate and specific than the once used by grading labs.
The grading parameters presented in this booklet give the customer a detailed overview of the diamond and its characteristics.
The parameters not only grade the diamonds in great detail but each component requires pinpoint precision on a consistent basis to establish crediblity.
There are now 17 grading attributes for ultimate accuracy. In order to uphold the failsafe accuracy and consistency in grading, which is ultimately the core, and the backbone of the system. Our affiliated cutting centre set various enabling systems.

The diamonds are valued more precisely on the basis of:

• Aid of around 500 Master Stones for reference and comparison and number of master stones growing (totaling over 2mln usd in value).
A Multi Tier Checking system ensuring that graders are always alert and impartial in the grading.
A motivational Incentive system ensuring that graders are always alert and impartial in the grading.
Accountability of each person with respect to each stone at every stage of grading.

Customers can therefore buy a diamond with the complete confidence that the diamond they select has been correctly assessed and therefore, accurately priced with regards to its quality.
Simply unmatched, filled with confidence and transparency, reliable, precise and dynamic above all, comprehensive is how one percieves the grading system. This is what makes it so special and unique.

CARAT
Across global markets, diamond prices are always stated in terms of per carat rate. Also, since diamond is quite an expensive commodity, a fluctuation of 1 or 2 cents in the weight causes fluctuations in price more particularly in the bigger sizes (i.e. above 1 carat). Specifying weight up to the third decimal digit offers crystal clear transparency regarding the pricing of individual diamond. Price difference, when measured after factoring in the third digit of a cent, accuracy in pricing is achieved. Third digit measurement eliminates possibility of rounding off of any fraction.

Due to our meticulous and precision oriented approach, the weight of each of our diamond is specified till the 3rd decimal digit, for e.g., 1.009Cts, instead of the conventional method of stating only till 2 decimal digits.

Size Weight in carats
3 P/C – 0.300 to 0.399
+0.40 – 0.40 0to 0.499
+0.50 – 0.500 to 0.699
+0.70 – 0.700 to 0.899
+0.90 – 0.900 to 0.999
+1.00 – 1.000 to 1.499
+1.50 – 1.500 to 1.999
+2.00 – 2.000 to 2.999

CLARITY
Since, diamonds are formed within the earth’s crust, under tremendous heat & pressure, they may either have some inherent flaws, or some solid particles or elements may get entrapped within a rough diamond. These internal ( inclusions) or external (blemishes) features as well as their size, nature, number, position & relief, with respect to the overall diamond, decide its clarity. Better the clarity, more transparent and clearer the diamond.

In our grading, ‘FL’ indicates the best & cleanest diamond without any internal inclusions or external blemishes, even when observed under a microscope.
In descending order, clarity grades are as follows:
IF, VVS1, VVS2, VS1+, VS1, VS2+, VS2, SI1+, SI, SI1-, SI2+, SI2, SI2-,
SI3+, SI3, SI3-, I1+, I1, I1-, I2+, I2, I2-, I3+, I3, I3-, I4+, I4, I4-, I5
and finally I6 which denotes an extremely included stone.

VVS, meaning Very Very Slightly included, very hard to spot with a 10x loupe
VS, meaning Very Slightly included, hard to spot with a 10x loupe
SI, meaning Slightly included, easy to spot with a 10x loupe
I, meaning visible to the naked eye

We provide a total of 32 clarity grades from FL to I6 whereas the other grading systems consider only 12 clarity grades.

CLARITY – Table Inclusion

This term explains the magnitude or the impact of the inclusion(s) (if any) in the table in comparison to the total inclusions in the diamond.
T0 indicates a table which is Almost Clean, T1, T2 and T3 in descending order, indicate tables with increasing proportions of inclusions visible through the table, and T4 denotes that most of the inclusions appear to be in the Table.

CLARITY – Black Inclusion
Black Inclusions are inclusions entrapped within a diamond and appear black in color. This attribute indicates the magnitude or the impact of black inclusion(s) (if any) on overall purity grade, as compared to the total inclusions in a diamond.

These inclusions are referred to as ‘Natts’ in common parlance.
N0 indicates there are almost no black inclusions in the diamond, N1, N2 and N3 in descending order indicating increasing proportions of Black Inclusions, and N4 denoting that most of the inclusions in a diamond are Black.

CLARITY – Inclusion Patern
This indicates how densely the inclusions are located within the diamonds, i.e. whether they are concentrated or in a scattered pattern.

S1 – Scattered Inclusion
S2 – Semi Scattered Inclusion
C1 – Light Concentrated Inclusion
C2 – Semi Concentrated Inclusion
C3 – Concentrated Inclusion

CLARITY – Internal Graining

These are naturally occurring lines, at times even clustered together indicating irregular growth of the diamond crystal during its formation. These line like structures usually transparent and invisible to the naked eye affect the clarity and hence the price of high clarity diamonds.

G0 indicates no internal graining in the diamond, G1 (Light Internal Graining) and G2 (Medium Internal Graining) indicate diamonds with increasing proportions of internal graining and G3 denotes Heavy Internal Graining.

CLARITY – Open’s

When an inclusion or a feather within a diamond is open near the surface, or if there is a chip, cavity, pit or natural on the surface, then such flaws are graded as ‘Opens’.

NN – No Open Inclusion
VS – Very Small Open Inclusion
SM – Small Open Inclusion
MD – Medium Open Inclusion
LG – Large Open Inclusion
VL – Very Large Open Inclusion
EL – Extra Large Open Inclusion

For ease of locating opens, TOP indicates Opens in the Table, COP indicates Opens in the Crown, and POP indicates Opens in the Pavilion.

COLOR
Natural diamonds consist of Carbon atoms which are colorless in nature. However, during formation or rough diamonds in the earth’s surface, atoms of elements like Nitrogen, Boron etc. may get attached to the Carbon atoms theryby giving a natural color tinge to the stone. Higher the presence of these atoms stronger the tinge & lower the color. Nitrogen cousing diamonds to tinge to yellow, Boron to blue.

Color is an important factor while valuing diamonds. It can range from colorless to yellow, brown, etc – the more colorless a diamond, the greater its rarity and value.

Exceptional White: D+, D, D
Rare White: E+, E, E-, F+, F, F
White: G+, G, G-, H+, H, H

OffWhite: I+, I, I-, J+, J, J
Light Tinted: K+, K, K-, L+, L, L-, M
Tinted: N, O, P, Q, R

Then come: Fancy Very Light, Fancy Light, Fancy, Fancy Intence, Fancy Vivid

Conventional grading systems usually cover only 32 color grades, but we provide a total of 44 color grades with the addition of ‘better (+)’ and ‘lower (-)’ grades between the standard color grade.

COLOR – Shade / Hue

At times, in a diamond crystal along with Carbon atoms Nitrogen or Boron atoms also form bonds which give rise to ‘color centers’, which radiate a deeper shade across the diamond, giving it a Hue or Tone.
Depending on the intensity of concentration at these color centers, VGS grades 12 color shades and all these sub-grades impact on the pricing, which is explained in the below example:

1. White (WH)
2. Off white (OWH)
3. Yellow (YL)
4. Brown (BR)
5. Yellowish Green (YLG)
6. Yellowish Brown (YLB)
7. Brownish Pink (BRP)
8. Pink (PN)
9. Pinkish Brown (PNB)
10. Green (GN)
11. Grayish Black (GBK)
12. Blue (BL)

LUSTER

Luster, also termed as Briliance of a diamond indicates the brightness of the incident light, reflected back from within the diamond, as a result of the combined preciseness of the size and angles of its table, crown & pavilion facets. At times, the rough diamond itself may inherently contain extremely miniscule but closely grouped bubble like structures or strands that may appear like a ‘cloud’ structure, which ultimately adversely affect light return of a diamond.

Level of Brilliance:
EX – Excellent Luster
VG – Very Good Luster
GD – Good Luster
FR – Fair Luster

Beside, some diamonds may have a little whiteness or cloudiness present in them. These are known as milky luster diamonds. Such diamonds are further cassified into sub categories depending on the extent of the milky effect in them, using the below terminologies:

Level of Milkiness:
ML1 – Very Slightly Milky
ML1.5 – Slightly Milky
ML2 – Medium Milky
ML2.5 – Medium Heavy Milky
ML3 – Heavy Milky
ML3.5 – Very Heavy Milky
ML4 – Strong Milky

FLUORESCENCE

Emission of visible light by a diamond when it is exposed to ultraviolet radiation is termed as Fluorecence. A very high fluorescence reduces the briliance of a diamond.

FL0 – No Fluorecence
FL1 – Faint Fluorecence
FL2 – Medium Fluorecence
FL3 – Strong Fluorecence
FL4 – Very Strong Fluorecence

FLUORESCENCE COLOR
Depending on the nature and type of bonds that other elements form with
carbon atoms of a diamond crystal, fluorescence can be of different
colors.
Fluorescence colors like white, blue, yellow, orange and green are having
direct impact on the overall color and hence the pricing of a diamond.

CUT

This is the only one of the 4Cs that is not created by Nature, but iscrafted by the skill of experienced craftsmen. Cut determines how a diamond reflects light, which in effect is responsible for the sparkle or brilliance, in turn majorly impacting its beauty.

The cut or the “make” of a diamond refers to the angles and proportions of all the facets created while transforming a rough diamond into a polished one.

The way of grading is the only grading method currently available that uses 3 additional aspects of Cut viz. Polish, Symmetry and Culet, each of which is further judged on the basis of its constituent five or more grades, thereby making for an accurate judgment.

The grades following 6 Cut grades and all these impact on the pricing.

HA – Heart & Arrow Cut
ID- Ideal Cut
EX – Excellent Cut
VG – Very Good Cut
GD – Good Cut
FR – Fair Cut

CUT – Polish
It is an overall condition of a finished / polished diamond’s facet surfaces. Each individual facet on a diamond has to be polished to give it the shiny mirror like surface which makes the diamond sparkle when light bounces off its surface, at different angles. The better the polish the more the
diamond will sparkle.

ID – Ideal Polish
EX – Excellent Polish
VG – Very Good Polish
GD – Good Polish
FR – Fair Polish

CUT – Symmetry
A diamond’s symmetry is the arrangement of the facets, its proportions and angles, resulted by the manufacturer. Better symmetry clearly indicates that a diamond has been manufactured not only with the utmost care, but also with a high level of perfection and accuracy. Better the symmetry, better is the light behavior which results in a attractive diamond. The Symmetry grades are as below:

ID – Ideal Symmetry
EX – Excellent Symmetry
VG – Very Good Symmetry
GD – Good Symmetry
FR – Fair Symmetry

CUT – Spread Ratio

Grading systems consider ‘spread’ as a crucial factor in grading diamonds, the term ‘Spread’ is an industry term which refers to a diamond’s face up size compared to its weight. One can also call this as ‘weight ratio’ or ‘millimetre footprint versus weight’.

“Theoretically, a standard or ideal Round Brilliant would have proportions such that a 1.00 Ct stone would have a diameter of 6.47mm. On comparing any other diamond with this ‘Ideal’ diamond, if it has zero or no spread, then this diamond would be equal in size, weight and
proportions to the Ideal diamond.”

In other words, for a given diameter negative spread indicates diamond weight(in % terms) being in excess of what it ideally should be, whereas in the reverse case, positive spread indicates diamond weight being lesser than what ideally should be. Spread considers overall weight and the diameter, so one need not remember the parameters like Girdle, Depth and Crown Height. If anywhere weight is more or less, it get reflect in the spread, making it a logical parameter for purchasing diamonds.

However, spread as a parameter for deciding to purchase diamonds functions as a precise indicator of whether a given diamond is actually justifying the price it is asking. In other words, to a customer, spread can clearly identify whether for a given price, a diamond is carrying more
weight than it ideally should, or less.

benefits of ‘spread / weight ratio’ as a parameter in diamond purchase:

It provides detailed information on the actual size and diameter of the diamond, which will have a direct impact on price. Two diamonds with similar parameters but with different spread will be different in price.
By considering overall weight and the diameter, one can focus less on parameters such as Girdle height, Total depth, Crown height and Pavilion depth; If anywhere, the weight is more or less than it will be reflected in the ‘spread’, making it a logical parameter for the diamond buyer.
‘Spread’ gives the buyer a better understanding as to how well the diamond has been cut and therefore its value.

More info on ‘spread’ and on how it is calculated is available upon request.

CUT – Culet
The bottom most point or vertex of the diamond where all the pavilion mains meet is termed as the culet. If all pavilion mains do not meet at this point, or if the culet is chipped or broken, it is termed as open, in which case, it would resemble a miniscule facet.

The Culet grades of the diamond are as follows:

grade    description
NN        No Open Culet
VS        Very Small Open Culet
SM        Small Open Culet
MD        Medium Open Culet
LG        Large Open Culet

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