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Alexandrite

Tsarstone collectors guide


Carat

Carat
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.
Bibliographic details
Page title Definition of Carat
Author David Weinberg
Website title Alexandrite Tsarstone Collectors Guide
Date published 03 July 2010 04:47 UTC
Date accessed 01 June 2026 04:16 UTC
Permanent link http://w.alexandrite.com/viewpage.html?id=GG-088-00002
AMA style
David Weinberg. "Definition of Carat". In Alexandrite Tsarstone Collectors Guide. July 03, 2010, 04:47 UTC. Available at: http://w.alexandrite.com/viewpage.html?id=GG-088-00002. Accessed June 01, 2026.
APA style
"Definition of Carat". (2010, July 03). In Alexandrite Tsarstone Collectors Guide. Retrieved 04:16, June 01, 2026, from http://w.alexandrite.com/viewpage.html?id=GG-088-00002.
Bluebook style
"Definition of Carat", http://w.alexandrite.com/viewpage.html?id=GG-088-00002 (last visited June 01, 2026).
Bluebook: Harvard JOLT style
See Alexandrite Tsarstone Collectors Guide, "Definition of Carat", http://w.alexandrite.com/viewpage.html?id=GG-088-00002 (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.) (as of Jun. 01, 2026, 04:16 GMT).
CBE/CSE style
David Weinberg. "Definition of Carat". In Alexandrite Tsarstone Collectors Guide. 2010 Jul 03, 04:47 UTC.[Internet], Alexandrite Tsarstone Collectors Guide; 2010 Jul 03, 04:47 UTC [cited 2026 Jun 01]. Available from: http://w.alexandrite.com/viewpage.html?id=GG-088-00002.
Chicago style
David Weinberg, "Definition of Carat", http://w.alexandrite.com/viewpage.html?id=GG-088-00002, (accessed June 01, 2026).
MLA style
"Definition of Carat". Alexandrite Tsarstone Collectors Guide. 03 Jul 2010, 04:47 UTC. 01 Jun 2026 http://w.alexandrite.com/viewpage.html?id=GG-088-00002
MHRA style
David Weinberg, "Definition of Carat", Alexandrite Tsarstone Collectors Guide, 03 July 2010, 04:47 UTC, http://w.alexandrite.com/viewpage.html?id=GG-088-00002 [accessed 01 June 2026].
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