Accessibility options

Switch to preferred accessibility theme:


Increase or decrease the text size:

  • Internet Explorer: View > Text Size > Largest

Keyboard navigation and access keys:

  • A - Accessibility options
  • 0 - Skip navigation
  • 1 - Home
  • 2 - Alexandrite chapters
  • 3 - Alexandrite directory
  • 4 - Alexandrite forums
  • 5 - Alexandrite gemstones
  • 6 - Alexandrite localities
  • 7 - Contact information
  • 8 - About Alexandrite Guide
  • 9 - Sitemap
  • Press ALT + Access Key, then ENTER.

Close

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 31 May 2026 20:59 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 May 31, 2026.
APA style
"Definition of Carat". (2010, July 03). In Alexandrite Tsarstone Collectors Guide. Retrieved 20:59, May 31, 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 May 31, 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 May. 31, 2026, 20:59 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 May 31]. 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 May 31, 2026).
MLA style
"Definition of Carat". Alexandrite Tsarstone Collectors Guide. 03 Jul 2010, 04:47 UTC. 31 May 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 31 May 2026].
Close options details