Carat

The carat of a diamond is actually a measure of the weight of the loose diamond.

1 carat = 200 milligrams

A carat is divided into 100 points.

So, as an example, 1 carat and 21 points is written 1.21 carats and would equal 1.21 x 200 milligrams = 242 milligrams. The larger the carat of the diamond, the more expensive that diamond is, with the other three Cs being equal.

 

More Carat = More Expensive

 

Remember, the carat of a diamond is the weight of the stone, not the size of the stone. However, there is an obvious relationship between carat and size for the common types of shapes for diamond.

A chart will again help you understand the cost implications of increasing or decreasing the carat of a diamond.

The chart below illustrates the change in price that accompanies the change in diamond carat, with the other 3 Cs being held equal, with a loose diamond, round shape, very good cut, F colour and VS1 clarity.

As larger diamonds are much rarer than smaller diamonds the increase in price is non-linear. Also, as the diamond carat reaches the whole numbers such as 1.0 or 2.0 carats, the price for the diamond increases at a faster rate approaching the whole carat weights. This is because wholesale diamonds tend to be priced in whole carats, which leads to the larger relative jump in price around these numbers and there is also an “exclusivity“ factor surrounding the whole carat numbers.

The size of the diamond is undoubtedly the most noticeable of the diamond’s characteristics. While it will be tempting to go for the biggest diamond available for your budget, you should bear in mind that despite what they say, size isn’t everything. The quality of a diamond is dependant on the other 3 Cs also.

The diamond carat is the C that is most easily able to be measured, as it is simply the weight of the diamond. This makes the carat an ideal C to use as a benchmark when evaluating diamonds. Hold the carat as a constant for different diamonds and then compare how differences in the other 3 Cs affect the cost of those diamonds.

Tips on Diamond Carat

When evaluating a diamond’s carat:

• Make sure the jeweller is using calibrated electronic jewellery scales to weigh the diamonds he/she is showing you. Check this measured carat against the carat that is on the laboratory certificate.

• Ask the jeweller what his/her opinion of the cut of the diamond is. A poorly cut diamond may hold its weight around its middle and therefore look smaller in diameter than what it should. In effect you will be paying more for a diamond that doesn’t look as big.