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AMA style

David Weinberg. "Definition of Zone axis". In Alexandrite Tsarstone Collectors Guide. July 03, 2010, 04:52 UTC. Available at: http://m.alexandrite.net/viewpage.html?id=GG-085-00003. Accessed April 03, 2026.

APA style

"Definition of Zone axis". (2010, July 03). In Alexandrite Tsarstone Collectors Guide. Retrieved 15:41, April 03, 2026, from http://m.alexandrite.net/viewpage.html?id=GG-085-00003.

Bluebook style

"Definition of Zone axis", http://m.alexandrite.net/viewpage.html?id=GG-085-00003 (last visited April 03, 2026).

Bluebook: Harvard JOLT style

See Alexandrite Tsarstone Collectors Guide, "Definition of Zone axis", http://m.alexandrite.net/viewpage.html?id=GG-085-00003 (A line runs through the center of a crystal, to which all faces of a given zone are parallel.) (as of Apr. 03, 2026, 15:41 GMT).

CBE/CSE style

David Weinberg. "Definition of Zone axis". In Alexandrite Tsarstone Collectors Guide. 2010 Jul 03, 04:52 UTC.[Internet], Alexandrite Tsarstone Collectors Guide; 2010 Jul 03, 04:52 UTC [cited 2026 Apr 03]. Available from: http://m.alexandrite.net/viewpage.html?id=GG-085-00003.

Chicago style

David Weinberg, "Definition of Zone axis", http://m.alexandrite.net/viewpage.html?id=GG-085-00003, (accessed April 03, 2026).

MLA style

"Definition of Zone axis". Alexandrite Tsarstone Collectors Guide. 03 Jul 2010, 04:52 UTC. 03 Apr 2026 http://m.alexandrite.net/viewpage.html?id=GG-085-00003

MHRA style

David Weinberg, "Definition of Zone axis", Alexandrite Tsarstone Collectors Guide, 03 July 2010, 04:52 UTC, http://m.alexandrite.net/viewpage.html?id=GG-085-00003 [accessed 03 April 2026].