Carat Weight

One carat is a unit of weight measurement equivalent to 1/5th of one gram. Most gemstones are priced and sold based on their carat weight. For average sized stones, this price is based primarily on their color, cut, and clarity. But as you begin to look at larger stones, and particularly larger stones of high quality, the 4th 'C' begins to play a much bigger role in pricing the stone. This is because the larger stones are rarer, and thus command a higher price per carat than smaller stones of the same quality. The mesurement is correctly abreviated as 'ct.'

With very small stones, sometimes the term point is used instead. In such cases, each point represents 1/100th of a carat, and is abbriviated as 'pt.'

In instances where a piece or parcel consists of multiple stones, the collective weight will be represented instead, in these cases, the term 'total carat weight' is used, and is abreviated as 'TCW'.

The term carat comes from the seed pods produced by the carob tree. In ancient times, common objects were often used as standards for comparison, and the weighing of gemstones was no exception. Naturally, because the weight of the pods would vary, shrewd traders of gemstones would have both pods to use when dealing their goods; one set for buying and another for selling. It wasn't until 1913 that the term was standardized into its present form.

During a visit with one of our sources, we were shown a 180 carat stone of rather poor color and clarity with large, obvious inclusions. A one carat stone cut from this material would be priced at less than $200. But a stone of this size is rare and commands a much higher price. In the case of this stone, our source had a buyer for it at $1,000/carat.

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