Carat Weight refers to the weight of a diamond. Carat is often confused with size, but it is actually a unit of weight.
A carat can also be divided into 100 “points”. A 0.75 carat diamond may also be referred to as a 75 point diamond or ¾ carat.

A one carat diamond does not cost exactly twice as much as a half carat diamond, since larger diamonds are rarer in nature, which places them at the top of the diamond quality pyramid, a one carat diamond will cost much more than double a half carat diamond for the same color, clarity and cut.

This parameter refers to the color of a diamond.

The color range of diamonds varies from icy white to warm white. Diamonds are graded according to a scale established by the Gemological Institute of America (GIA) that goes from D (colorless) to Z. The colors indicated in the table are only to show the differences in shades. The letter D refers to perfectly colorless stones, the rarest and most expensive. Below we have the color E (exceptional white), F (extra white +), G (extra white), H (white), IJ (slightly colored white), KL (colored white), MNOPRSZ (colored).

Clarity is measured by the amount of inclusions present in a diamond. Almost all diamonds have inclusions, sometimes called “nature’s fingerprints.” These are natural identifying features, like minerals or fractures, that appear during the formation of diamonds underground. They can take the form of small crystals, clouds, or feathers, but are usually not visible to the naked eye.

To see inclusions, jewelers must use a magnifying glass that allows them to view a diamond magnified 10 times so they can better locate inclusions. The location of an inclusion can help determine the value of a diamond. There are very few diamonds in nature that are completely free of imperfections and these are therefore extremely valuable.

Inclusions are rated on a scale of perfection, known as clarity, established by the Gemological Institute of America (GIA). Some inclusions may be hidden by the setting and therefore have little effect on the beauty of the stone. An inclusion in the center or table of the diamond may affect the dispersion of light, thus decreasing the brilliance of the stone. The higher the clarity of the diamond, the greater the brilliance, value, and rarity of the stone.

 

The cut is the only one of the 4Cs that is influenced by the hand of man. Based on mathematical formulas, a well-cut diamond will reflect light internally from one facet to another like in a mirror and then disperse and reflect it through the crown and table.

Cut can also refer to shape, for example round, square, teardrop, heart.
Because a round diamond is symmetrical and able to reflect virtually all of the light that enters it, this is the most brilliant shape and follows specific guidelines regarding proportions.

DIFFERENCE BETWEEN DIAMOND AND BRILLIANT

Many people confuse the word "diamond" with the word "brilliant". The Diamond is the precious stone of extreme value; the brilliant is a type of cut (the round cut) that for its characteristics allows the best brilliance. So any stone, for example zircon, can have a brilliant cut, but it has nothing to do with the diamond stone.