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Tsarstone collectors guide


A unit employed in weighing diamonds, pearls, and other gemstones, which formerly ranged from 185.5 to 205.3 milligrams. Now the International metric carat is equal to 0.2 gram, or 200 milligrams and this is the standard in a majority of countries. Abbreviation: c. The unit carat since April first 1914 was standardized worldwide as the metric carat. The term carat is derived from the seed of the Carob tree or Ceratonia siliqua. Also known as the locust tree in the Middle East. The dried seeds are very uniform in weight and were used by ancient pearl merchants as units of weight. Less uniform in weight is the seed of an orange, kidney-shaped with a black spot at one end, which was obtained from the so-called Coral tree or Erythrina corallodendron. The carat is divided into 4 grains.
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