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Article: Carat (mass)

Carat (mass)

Etymology and History

  • The word 'carat' comes from the Italian 'carato', which was derived from the Arabic 'qīrāṭ', borrowed from the Greek 'kerátion'. 'Kerátion' means carob seed, which is a diminutive of 'keras' meaning horn.
  • Carob seeds were originally used to measure jewelry, but they were not actually consistent in mass distribution.
  • Different countries had their own carat measurements in the past.
  • In the 1570s, carat began to be used for measuring diamond weights.
  • Today, the carat is used for measuring gemstones and pearls.

Standardization and Historical Definitions

  • In 1871, an international carat of 205 milligrams was proposed.
  • In 1907, a metric carat of 200 milligrams was proposed and accepted.
  • The metric carat became compulsory by law in France and was later adopted by the United States and the United Kingdom.
  • Different locations had slightly different mass values for the carat in the past.
  • The international carat of 205 milligrams became widely adopted, but some locations had specific carat values.

UK Board of Trade

  • The original Board of Trade carat was approximately 205 milligrams.
  • In 1888, the Board of Trade carat was changed to approximately 205 milligrams.
  • Some metric countries used the Board of Trade carat, even though it was a non-metric unit.
  • The Board of Trade carat was divisible into four diamond grains.
  • The Board of Trade carat was primarily used for measuring gold and had limited application.

Carat as a Unit of Mass

  • Carat is a unit of mass used for measuring gemstones and pearls.
  • It is equivalent to 200 milligrams or 0.2 grams.
  • The term 'carat' originated from the carob tree seeds which were used as counterweights on balance scales.
  • The carat weight affects the value and price of gemstones, with larger carat weights being more valuable.
  • The carat weight is often used in conjunction with other factors like cut, color, and clarity to determine the quality of a gemstone.

Carat vs. Karat and Conversion

  • Carat, as a unit of mass, should not be confused with 'karat', which is used to measure the purity of gold.
  • Karat is a measure of the proportion of gold in an alloy, with 24 karat being pure gold.
  • Carat and karat have different origins and meanings.
  • Carat can be converted to other units of weight, such as grams or ounces.
  • 1 carat is equal to 0.2 grams or 200 milligrams.
  • In the Imperial system, 1 carat is approximately equal to 0.007055 ounces.

Carat (mass) Data Sources

Reference URL
Knowledge Graph

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