What is a Carat?

At various times in their lives, most people have shopped for jewelry either as gifts for themselves or for their loved ones. For those who are not so familiar with precious gemstones or gemology terms, the task of finding the right jewelry for your budget could be quite daunting. For instance, you may have wondered why one piece of jewelry adorned with a single diamond is more expensive than one with smaller but multiple stones. Then again, you may have found it puzzling when your jeweler tells you that one of the two diamond engagement rings that you are contemplating to buy has a higher price tag despite the information that both diamonds are of the same quality and appears identical to the eye. In both cases, the difference in jewelry cost is affected by the diamond carat size. Perhaps, you may want to ask: “What is a carat?”

A carat is simply a unit of weight by which diamonds and other precious stones are measured. One carat is equivalent to twenty percent or one-fifth of a gram and can be expressed under the metric system as 0.20 grams. Stated in another way, five carats equals one gram or 1000 milligrams. Diamonds that weigh less than one carat are usually measured in points, where one point is equivalent to one percent or one hundredth of a carat. In this case, a half-carat diamond stone can be described as a 50-point diamond, which is another way of saying that the diamond is 0.50-carats. Knowing what a carat is, you may now want to ask: “What is a carat in relation to the price of a diamond jewelry?”

While the cut, clarity and color of the diamond affect its desirability, the carat impacts on its price simply because it refers to the actual weight or mass of the gemstone. This is so because the weight of the diamond is indicative of the rarity of the gemstone. Hence, the more carats a diamond has, the heavier it is, and the more expensive it becomes. At this point, it should be emphasized that the carat to price relationship is not linear but rather exponential. This means that the price jumps dramatically as diamonds increase in size. A 1-carat diamond, for instance, is substantially more expensive that a 0.95-carat stone although the difference between the two stones is practically indistinguishable to the naked eye. Knowing what is a carat could save you a lot of money if you are on a budget. It makes a lot of practical sense to choose a diamond that is just a fraction lighter than a whole carat or purchase a ring with multiple small diamonds than one that is adorned with one large stone.