What is a Carat?
By Brooke Denham 
, Thursday, May 03, 2012 2:37 AM
If you are shopping for a diamond or diamond jewelry, most likely you have heard the word carat or karat thrown around quite a bit. The former refers to weight and the latter to purity. Each of these terms has its own distinct definition, although they are both derived from the same word. And both are very different from the common vegetable, the carrot, and the ^ symbol used in editing , the caret.
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| Carob and Diamond on Scale |
The definition of carat is “a unit of weight in gemstones” and equates to 1/5 of a gram. The history of the word is quite interesting. The word carat comes from the Greek word for carob seed. Carob seeds were long ago used as a unit of weight. It was originally thought that this was because all carob seeds were relatively similar in weight. This, in fact, was not true. According to Wikipedia, it is said that, in order to keep regional buyers and sellers of gold honest, potential customers could retrieve their own carob seeds on their way to the market, to check the tolerances of the seeds used by the merchant. If this precaution was not taken, the potential customers would be at the mercy of “2 sets of carob seeds”. One set of “heavier” carob seeds would be used when buying from a customer (making the seller’s gold appear to be less). Another, lighter set of carob seeds would be used when the merchant wanted to sell to a customer. Today, a carat is said to be equivalent to 200 milligrams. It measures the mass or weight of gemstones and pearls. When it comes to picking out a stone for an engagement ring, to some people the diamond carat weight is the most important factor in their purchase. To other consumers, the term carat is just one of the 4Cs; carat weight, cut, clarity and color. The educated diamond buyer will weigh all four of these important characteristics before choosing a diamond.
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| Carob and Diamond With Loupe |
The term karat has a slightly different meaning. It too came from the carob seed, but became a variant dealing strictly with gold. Its definition states that a karat is “a unit for measuring the fineness of gold, pure gold being 24 karats fine”. Pure gold is extremely soft and when used in jewelry can easily be damaged. Therefore, copper, or another metal alloy is mixed with the gold. 24 karat gold is completely pure, while 18 karat gold will have 18 parts gold and the other six parts will be the other alloy (75% pure). 14 karat gold would be 14 parts gold and 10 parts alloy, and so on. In the United States of America, karat markings are always designated with a “K”, never a “C”. Stamping of gold purity on jewelry items is regulated by law.
These distinctions between carat and karat should help to clear up any confusion of the terms. This knowledge is definitely essential when making any significant jewelry purchases. It always pays to know the lingo!
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