What is GIA 4 C’s DIAMOND?


Every diamond has its own unique characteristics. The 4Cs — Color, Clarity, Cut, and Carat weight —are the internationally acknowledged standards for determining a diamond's quality.


The GIA color-grading system for diamonds starts with the letter D, which stands for colorless, and progresses to the letter Z, which stands for pale yellow or brown. The color appearance of each letter grade is well specified. Under regulated lighting and precise viewing conditions, diamonds are color-graded by comparing them to stones of known color.

  • • Colorless — D, E, F.
  • • Near Colorless — G, H, I, J.
  • • Faint — K, L, M.
  • • Very Light — N, O, P, Q, R.
  • • Light — S, T, U, V, W, X, Y, Z.
D The highest color grade is D, meaning it has nearly no color. D color diamond appears colorless under magnification and to the naked eye.
E An E color is the second-best color of diamond colors. E color diamonds look almost similar to D color diamonds. Sitting squarely in the middle of the elite “colorless” range (DEF), this particular color grade is virtually indistinguishable from perfectly colorless.
F An F color diamond is high on diamond color scale, known as “colorless” by gemologists which includes D, E and F colors. There are only 2 color grades higher than F color, while there are 20 grades lower than an F color diamond. F color is almost identical to D and E color diamonds, with nearly no visible color.
G The G color grading is the highest & best grade in the “Near Colorless” range of the GIA’s scale, which includes diamonds graded G to J.
G color diamonds have some tints of color, although they’re almost impossible to see with the naked eye.
H The GIA's color scale places H color diamonds in the "near-colorless" category. They appear nearly colorless, but when seen under magnification by an expert gemologist, they may display a little yellow tint.
I The I color grade is the second-lowest in the near-colorless range. Diamonds with the I color are ones that are in the middle of the Near Colorless category. I color however, lower range of white but not too yellow.
J J color diamonds appear colorless to the naked eye, but have a slight yellow tint that is visible under bright lights and magnifying glass. J color diamonds can be excellent choice in terms of value for money.
K - L - M On the GIA's diamond color scale, K-L-M color diamonds are classified as "faint tint," K-L-M colors are simply a "breakpoint" between near colorless and faint yellow. Which means they have a slight yellow tint that may be seen with the naked eye.
N - R Diamonds in the N to R category have easily noticeable yellow or brown tinting. These diamonds are available at a much lower price point than faintly tinted or near colorless diamonds.
S- Z Diamonds of an S-Z range is very close to fancy color diamonds.

2. CUT

The ‘Cut’ is the most quintessential characteristic of a diamond quality that impacts a diamond’s exquisiteness. Diamond-Cut especially relates to the quality of a diamond’s angles, proportions, symmetrical facets, brilliance, fire, scintillation, and finishing details. Also, more than any other aspect, the cut determines the beauty of the stone & add value to diamond jewelry.

The ideal and excellent grades, as per the diamond shape, shows symmetries, and angles cut for maximum brilliance and fire. The GIA diamond cut chart grades diamond cut on the scale of

Ideal - Excellent, Very Good, Good, Fair, and Poor.

  • • Brightness: A diamond reflects both internal and external white light.
  • • Scintillation: The quantity of sparkle a diamond creates, as well as the pattern of light and dark areas formed by reflections within the diamond.
  • • Fire: The dispersion of white light into all the colors of the rainbow.


A professional gemologist at the GIA reviews each diamond under magnification to determine the Cut grade. Here are the GIA diamonds cut grades:

Excellent Excellent Cut Diamonds have even more fire and luster of any diamond
Very Good Very Good Cut Diamonds are known for their brightness and fire. Very Good diamonds appear to sparkle similarly to Excellent diamonds with naked eye
Good Good Cut Diamonds represents brilliance and sparkle, with much of the light reflecting through the table to the viewer’s eye.
Fair Light easily departs through the bottom and sides of a fair cut diamond, resulting in minimal brilliance.
Poor Poor cut diamonds have almost no radiance, brilliance, or fire.


Diamond clarity refers to the presence and visual appearance of internal characteristics of a diamond known as inclusions, as well as surface defects known as blemishes. One of the 4Cs of grading is clarity.

Diamonds with higher clarity grades are more valuable, with the extremely rare "Flawless" graded diamond commanding the highest price.

  • FL (Flawless) No inclusions and no blemishes visible under 10x magnification
  • IF (Internally Flawless) No inclusions evident under 10x magnification
  • VVS1-VVS2 ( Very, Very Slightly Included ) Inclusions so slight they are tough for a skilled grader to see under 10x magnification
  • VS1-VS2 ( Very Slightly Included ) Inclusions are noticeable with effort under 10x magnification, but can be classified as minor
  • SI1-SI2 (Slightly Included) Inclusions are noticeable under 10x magnification
  • I1-I2-I3 (Included) Inclusions are visible under 10x magnification which may impact transparency and brilliance


Diamond clarity refers to the presence and visual appearance of internal characteristics of a diamond known as inclusions, as well as surface defects known as blemishes. One of the 4Cs of grading is clarity.

The carat weight of a diamond is used to determine its size. Because one carat is divided into 100 points, a diamond weighing 75 points weighs 0.75 carat. As larger diamonds are rarer and more valuable, their price rises with their carat weight.

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