| Carat (mass) |
Article Index for Carat |
Information AboutCarat (mass) |
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The carat is a unit of '', page 20, 6 May 2006 . Thus, the carob seed was used as a weight not because it was Naturally More Uniform in weight, but because it could be more easily standardized. In past centuries, different countries each had their own carat unit, all roughly equivalent to the mass of a carob seed. In the United Kingdom , before 1888 , the Board of Trade carat was exactly Grain s;The pre-1888 Board Of Trade carat, of which there were exactly per Ounce Troy , was approximately 205.4094 mg. after 1887 , the Board Of Trade carat was exactly grains.The post-1887 Board of Trade carat, of which there were exactly 151½ per ounce troy, was approximately 205.3035 mg. Despite it being a non-metric unit, a number of metric countries used this unit for its limited range of application. In 1907 , the definition of the '''metric carat''' of 200 milligrams was adopted at the Fourth General Conference On Weights And Measures ; this replaced the non-metric carat definition in the United States on July 1 , 1913 , and superseded the Board of Trade carat in the United Kingdom on 1 April 1914 . The metric carat is the one that is universally used today. The carat is divisible into one hundred ''points'' of two milligrams each. The Board of Trade carat was divisible into four ''diamond grains'',Unlike the modern carat, the Board of Trade carat was not used for measuring pearls; those were measured with ''pearl grains''. but measurements were typically made in multiples of carat. There were also two varieties of ''refiners’ carats'' once used in the United Kingdom — the pound carat and the '''ounce carat'''.The refiners’ carats were the offspring of the Carat As A Measure Of Fineness For Gold . The Pound Troy was divisible into 24 ''pound carats'' of 240 grains troy each; the pound carat was divisible into four ''pound grains'' of 60 grains troy each; and the pound grain was divisible into four ''pound quarters'' of 15 grains troy each. Similarly, the Ounce Troy was divisible into 24 ''ounce carats'' of 20 grains troy each; the ounce carat was divisible into four ''ounce grains'' of 5 grains troy each; and the ounce grain was divisible into four ''ounce quarters'' of 1¼ grains troy each.Chaffers, William. 1883 . ''Hall Marks on Gold and Silver Plate''. 6th edition. London : Bickers & Son. For Diamond s, a ''paragon'' is a flawless stone of at least 100 carats (20 G ). The ANSI X.12 EDI standard abbreviation for the carat is CD. EXTERNAL LINKS
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