Carat is the standard until of weight for diamonds. The word “carat” is derived from “carob”, the tree whose seeds became the standard for measuring diamonds.
One carat equals 1/5 of gram or .007 of an ounce. Carat weight is further divided into decimals. For example exactly ½ carat is .50 and expressed as 50 points. Therefore, a 1 carat diamond is made up of 100 points.
All other things being equal, as weight increases, so does a diamond’s rarity and value.
Color grading is standardized using the GIA color grading system. Color in a diamond is more accurately described as “lack of color”. Most diamonds occur in nature having impurities causing them to have slight yellowish cast.
Colorless diamonds are quite rare in nature and are therefore the most expensive. The GIA scale beings with the letter D and ends with Z For white stones. This scale ranges from colorless to yellow.
Most diamonds have some flaws “inclusions” which affect their clarity. Or the way that light is reflected through the stone. An ‘inclusion’ can be bubble. Spot or line which occurred while the diamond was being formed deep in the earth, and most are not visible to naked eye.
Diamonds are graded from flawless to imperfect based on how many inclusions there are and how visible each is. The fewer flaws a diamond has, the more valuable it is.
Most people confuse cut with the shape of a diamond. The shape you select is a matter of individual taste, and today your choice is limited only by the skill and imagination of craftsman. The cutting grade is determined by the effort to maximize the reflection of light during every stage of the fashioning process.
Most brilliant or fancy cut possess 58 carefully angled surfaces called facets, whose placement will affect the fire brilliance and ultimate beauty of your diamond.