Carat Diamond in its original form, before it is polished and shaped is called rough diamond or just rough. About half of the world’s rough diamond comes from central or south Africa. In addition there are significant diamond deposits in Russia, Canada, Brazil Australia and India. There are approximately 130 million carats of diamonds mined annually. The carat is the unit of weight that is used to measure and quantify all diamond. All diamonds whether in the rough form before polish or after as a finished gem are sold “per carat”. The carat is one of the four criteria used to describe and value all diamonds. The others of course are color, clarity and cut. The De Beers Corporation created these 4C’s in 1939 as a ways to standardize the description and value of all gem quality diamonds. Historically, the word “carat’ comes from the Greek “fruit of the carob”. The carob is a seed, which was used as the standard unit of measure on scales for thousands of years. The carob seed was used because of the belief that all carob seeds were uniform in weight. Today however, a carat is defined as the weight of two hundred milligram’s and is divided into one hundred points of 2 milligram’s each. It is for this reason that we say there are one hundred points in one carat of diamond. As such, .50 points would be a half a carat, .25 points a quarter carat, .75 points three quarters of a carat and so on. In the mining of diamonds there are significantly more smaller rough diamond found than larger rough diamond and so and diamonds are bought and sold throughout the world, smaller diamonds cost less money “per carat” than larger diamonds. This difference in price, which can be substantial in the total cost of a stone, is due in part to the market conditions of supply and demand. Thus, all diamonds are grouped according to size. Stones between 1 to 4 points have the same “per carat” price given that color, clarity and cut remain the same. The same stones between 5 and 7 points have a different “per carat” price. These price breaks continue, as the diamonds get bigger. Diamonds between 8 and 11 points are priced less than those between 12 and 14 points, diamonds between 14 to 18 points are priced less “pre carat” than those 18 to 22 and so on. These price breaks continue throughout the entire range of diamonds and continue more prominently as diamonds cross the full one-carat size. These differences in the price per carat of a diamond solely related to its size or carat can have a dramatic effect on its price. If we use a quarter carat, half-carat and three quarter carat diamond as an example, we can illustrate this difference. A quarter carat diamond, H in color and SI1 clarity, a nice white stone with some imperfections in the stone, none of which would be visible to the naked eye could cost about $225.00 dollars. The same quality stone in a half-carat size about $900.00 dollars and a larger stone of .75 points about $1500 .00 dollars. To further the example, that same stone as a one-carat diamond would be close to $4000.00 dollars but as a .90-carat, (just under a carat) it would cost just $3000.00 dollars. That’s a difference of about $1000.00 dollars for 10 points in size which will not be seen once that diamond is put into a ring. The same differences in prices would hold true regardless of what colors and clarities we chose. The only variable here was the carat weight or size of the diamond. While decisions about the size and look of a diamond are always very personal and important, a real understanding of each of the 4C’s, carat, color, clarity and cut can give invaluable information to anyone interested in learning about or purchasing a diamond.