Basic tips - 4C - Diamond Knowledge - SY Diamond
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Diamond basic attributes – the 4Cs

4C represents Color, Clarity, Cutting and Carat. The 4Cs are the shared common attributes used by different grading institutes, to determine the quality and value of each diamond. Therefore, it is crucial to know the 4Cs before buying a diamond.

1) Carat

Carat is the weighting unit of a diamond, as below:
1 carat = 0.2 grams = 0.007 oz.

Bigger diamonds are rarer, as such, the value per carat will also be higher. For example, the value of a 1 carat diamond would be much higher than the total of two 0.5 carat diamonds.

The weight of a diamond affects its size, although the same weight may lead to different sizes, the following table shows the approximate size to weight ratio:

2) Clarity

Diamond with no magnification Diamond at 10x magnification

Clarity refers to the inclusion and blemishes of a diamond; the level of clarity is determined by the number, size, place, whether it is obvious and the general effect of those inclusions and blemishes to the appearance of a diamond. Since diamonds are formed naturally, the formation process would usually include some other substances which lead to so called crystals, feathers inside a diamond. Better clarity gives a higher value of a diamond.

The GIA Clarity Scale contains 11 grades. In determining a clarity grade, the GIA system considers the size, nature, position, color or relief, and quantity of clarity characteristics visible under 10× magnification.


Flawless (FL) - No inclusions or blemishes are visible to a skilled grader using 10× magnification

Internally Flawless (IF) - No inclusions and only blemishes are visible to a skilled grader using 10× magnification

Very, Very Slightly Included (VVS1 and VVS2) - Inclusions are difficult for a skilled grader to see under 10× magnification

Very Slightly Included (VS1 and VS2) - Inclusions are minor and range from difficult to somewhat easy for a skilled grader to see under 10x magnification

Slightly Included (SI1 and SI2) - Inclusions are noticeable to a skilled grader under 10x magnification

Included (I1, I2, and I3) - Inclusions are obvious under 10× magnification and may affect transparency and brilliance


Since the diamond with “Included” grading includes quite obvious inclusion, we do not recommend and also do not offer diamonds with Grade I1 , I2 & I3 , except customers request us to provide.

3) Color

It refers to the level of colorless of a diamond. The rating is from D to Z. For D color, the best color level, representing colorless and continues with increasing presence of color to the letter Z, or light yellow or brown, as shown below:

D E F G H I J K L M N O P Q R S T U V W X Y Z
COLORLESS NEAR COLORLESS FAINT YELLOW VERY LIGHT YELLOW LIGHT YELLOW

Many of these color distinctions are so subtle as to be invisible to the untrained eye. But these slight differences make a very big difference in diamond quality and price.

4) Cutting

Color and clarity are born naturally with a diamond; however, on the other hand, Cutting is determined by the craftsmanship the diamond receives, which is an important factor to lead the diamond to sparkling perfection. The cutting factor involves complex determination, as a value factor, though, it refers to a diamond’s proportions, symmetry and polish.

Too Shallow Ideal Cut Too Deep

The proportions of a diamond refer to the relationships between table size, crown angle and pavilion depth. A wide range of proportion combinations are possible, and these ultimately affect the stone’s interaction with light.

GIA diamond graded cutting into 5 categories, from Excellent to Poor.