The 4 C’s.
The size or weight of the diamond has the greatest impact on the price. One (1) carat, equivalent to 0.20 grams, is the standard weight for diamonds and most other precious stones. If all other characteristics of the diamond are equal, the weight of the stone determines its value. There are different names for a diamond of 1 carat: 1 ct, 100 points or ‘4-greiner’ (this is only used by professionals). It is very important to note that the carat weight of a diamond is not used to identify with its size; ‘carat’ is only used as a function of the weight.
Why this distinction?
Because weight can be hidden in various parts of the stone.
We can talk about one as an example:
Good sharps Deep sharps Straight sharps
Sometimes stones with equal weight can show larger or smaller, depending on how it is made. The price of a diamond is expressed per carat, e.g., 1.25 ct x $ 1000 per carat, the total price for this 1.25 carat stone is $ 1250.
How big is a carat?
To give you an idea of the true size of a diamond (and now we have only about brilliant cut, please take a look at the following “approximate” table for the sizes:
The purity of a diamond refers to how “clean” or how “pure” it is.
The purer, the higher the price. Most diamonds have inclusions, flaws. The quantity and size of inclusions or flaws determine the quality of the diamond. For example, a small black inclusion which is visible to the naked eye may have a smaller impact on the brilliance of the diamond than a big white rupture that is not directly visible.
IF or LCL: This diamond has no inclusions, even when viewed with a loupe (special diamond magnifying glass) with a magnification x 10.
VVS1 or VVS2: This diamond has ‘Very, Very Small’ inclusion, visible only by an expert with a magnification x 10.
VS1 and VS2: This diamond has ‘Very Small’ inclusion, even with x 10 magnification it’s hard to see by a layman.
Si1 or Si2: these diamonds have inclusions that are visible with a magnification x 10.
P1 or P2 or P3: Quite large inclusion, according to grade with naked eye.
The colour of a diamond has the second largest impact on price. Did you know that diamonds occur in all colours of the rainbow? Colour determination is very difficult. The closer to colourless, the more expensive. Most diamonds have a slight yellow or brown colour, except for fancy colours, which can be intense yellow, blue, pink or red.
When no fancy colour diamond, the degree of the colour is set on a scale starting from “no colour” (D) to “light yellow” or “light brown” (Z). A “D” colour is considered a colourless diamond. If the colour is darker than “Z” colour, it is considered a fancy colour. A fancy colour (e.g., deep-yellow) is much rarer and therefore more expensive than a “Z” colour.