A diamond carat is the internationally recognised unit of measurement used to specify the stone's weight.
A diamond carat is the internationally recognised unit of measurement used to specify the stone's weight.
Many people believe carat refers to a diamond's size, not its weight. Another misconception is that a larger carat weight is always better than a smaller carat weight. But a high carat weight diamond with a poor cut may look smaller and have less sparkle than a diamond with a lower carat weight and a very good cut.
The term carat comes from the Ancient Greek and Arabic method of weighing precious metal and stones against the beans of the carob tree. Each of the tree's long green beans contained seeds, which were considered to be even in weight. One seed equalled one carob, which is likely where the term carat originates.
It wasn’t until 1907, at the Fourth General Conference on Weights and Measures, when it was agreed upon that one diamond carat would be equal to 200 mg, or .2 grams, of a diamond.
In 1913 the United States officially accepted the carat as the gemstone measurement, closely followed by the United Kingdom and Europe a year later. By the 1930s, the majority of the diamond and gemstone industry had agreed to the standardised measurement.
Rough diamonds come in all shapes and sizes, as well as different colours and purities. The larger, whiter and cleaner the diamond, the more rare it is.
Therefore, the cost per carat of a large diamond with the same colour, clarity and cut will cost more than a smaller diamond. But that doesn't mean to say the price per carat of diamonds is steady, as they can increase exponentially. For example, a 1 carat diamond would be valued higher than two 0.50 carat diamonds of the same quality.
Even so, some diamond cutters will sacrifice brilliance to maximise profit, as more carat weight generally means more money. This means that diamonds cut poorly to maximise size could quite easily be dull and lifeless - weight alone does not equal beauty.
Other diamond cutters will intentionally sacrifice weight so they can focus on a better cut and thus obtain brilliant diamonds that sparkle and shimmer. If they are of a slighter lower carat weight, they could be available at a more affordable price.
So what carat weight is right for you? Well, a lot depends on personal preference and budget. Just remember that with diamond rings, the most visible aspect of the stone will be its surface area at the top.
You should also consider the diamond’s cut and diameter, as this will have an impact on its aesthetic. Carat has the biggest effect on a diamond’s price, but more expensive doesn’t always mean better stone.