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AMA style

David Weinberg. "Definition of Volcanic glass". In Alexandrite Tsarstone Collectors Guide. July 03, 2010, 04:43 UTC. Available at: http://m.alexandrite.net/viewpage.html?id=GG-081-00003. Accessed April 03, 2026.

APA style

"Definition of Volcanic glass". (2010, July 03). In Alexandrite Tsarstone Collectors Guide. Retrieved 15:39, April 03, 2026, from http://m.alexandrite.net/viewpage.html?id=GG-081-00003.

Bluebook style

"Definition of Volcanic glass", http://m.alexandrite.net/viewpage.html?id=GG-081-00003 (last visited April 03, 2026).

Bluebook: Harvard JOLT style

See Alexandrite Tsarstone Collectors Guide, "Definition of Volcanic glass", http://m.alexandrite.net/viewpage.html?id=GG-081-00003 (A solid volcanic natural form of glass (rock) produced by sudden cooling and solidification of viscous lava before crystallization can take place, such as obsidian, pitchstone or other glassy masses. Obsidian is used for tumbled gems, ornamental objects, beads and cut cabochon, some pieces have been faceted.) (as of Apr. 03, 2026, 15:39 GMT).

CBE/CSE style

David Weinberg. "Definition of Volcanic glass". 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 03]. Available from: http://m.alexandrite.net/viewpage.html?id=GG-081-00003.

Chicago style

David Weinberg, "Definition of Volcanic glass", http://m.alexandrite.net/viewpage.html?id=GG-081-00003, (accessed April 03, 2026).

MLA style

"Definition of Volcanic glass". Alexandrite Tsarstone Collectors Guide. 03 Jul 2010, 04:43 UTC. 03 Apr 2026 http://m.alexandrite.net/viewpage.html?id=GG-081-00003

MHRA style

David Weinberg, "Definition of Volcanic glass", Alexandrite Tsarstone Collectors Guide, 03 July 2010, 04:43 UTC, http://m.alexandrite.net/viewpage.html?id=GG-081-00003 [accessed 03 April 2026].