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AMA style

David Weinberg. "Definition of Ultramafic". In Alexandrite Tsarstone Collectors Guide. July 03, 2010, 04:43 UTC. Available at: http://w.alexandrite.net/viewpage.html?id=GG-080-00001. Accessed April 09, 2026.

APA style

"Definition of Ultramafic". (2010, July 03). In Alexandrite Tsarstone Collectors Guide. Retrieved 07:56, April 09, 2026, from http://w.alexandrite.net/viewpage.html?id=GG-080-00001.

Bluebook style

"Definition of Ultramafic", http://w.alexandrite.net/viewpage.html?id=GG-080-00001 (last visited April 09, 2026).

Bluebook: Harvard JOLT style

See Alexandrite Tsarstone Collectors Guide, "Definition of Ultramafic", http://w.alexandrite.net/viewpage.html?id=GG-080-00001 (A type of igneous rock characterized by a high content of mafic minerals, particularly olivine, pyroxenes, amphiboles, etc. The silica content is less than 45%.) (as of Apr. 09, 2026, 07:56 GMT).

CBE/CSE style

David Weinberg. "Definition of Ultramafic". In Alexandrite Tsarstone Collectors Guide. 2010 Jul 03, 04:43 UTC.[Internet], Alexandrite Tsarstone Collectors Guide; 2010 Jul 03, 04:43 UTC [cited 2026 Apr 09]. Available from: http://w.alexandrite.net/viewpage.html?id=GG-080-00001.

Chicago style

David Weinberg, "Definition of Ultramafic", http://w.alexandrite.net/viewpage.html?id=GG-080-00001, (accessed April 09, 2026).

MLA style

"Definition of Ultramafic". Alexandrite Tsarstone Collectors Guide. 03 Jul 2010, 04:43 UTC. 09 Apr 2026 http://w.alexandrite.net/viewpage.html?id=GG-080-00001

MHRA style

David Weinberg, "Definition of Ultramafic", Alexandrite Tsarstone Collectors Guide, 03 July 2010, 04:43 UTC, http://w.alexandrite.net/viewpage.html?id=GG-080-00001 [accessed 09 April 2026].