The most defining characteristic of any diamond is its cut. This determines the symmetry of the stone, its overall proportions and its ability to reflect light.

How a diamond cutter cuts and polishes a diamond will affect the amount of sparkle and brilliance that comes from the stone when it interacts with light.

How light strikes the surface, how much enters the diamond and in what form that light returns to your eye — cut dictates all this and more.

A polished diamond’s proportions affect its light performance, which in turn affects its beauty and appeal.


Diamonds come in a variety of colours, ranging from rare, clear diamonds to those that have a yellow or brown tint. The less colour, the higher the grade.

A universal colour scale classifies diamonds from D (colourless) to Z (light yellow or brown).

Diamonds without colour are rare. Most diamonds used in jewellery are nearly colourless, with pale tints of yellow or brown.


The industry determines the size of a diamond by weight, measured in carats.

One diamond carat weighs 200 milligrams. The industry weighs smaller diamonds using a point system, with every 100 points being equal to 1 carat.

Larger diamonds are rarer than smaller diamonds, so all other factors being equal, a single 1-carat stone is worth more than four quarter carat stones put together. However, the worth of a diamond is determined by all of the first four Cs. Size alone does not determine value.


Clarity refers to how perfect the stone is. Almost all diamonds have some internal imperfections (such as pinpoints and crystals) called inclusions, and some external blemishes (such as scratches and chips) or both.

The fewer flaws a gemstone has, the higher its clarity grade and the more valuable it is.

Most diamonds have flaws that the naked eye can see only with the help of high-powered magnification. These flaws do not affect the splendor of the diamond.