{{Short description|Light-colored zircon variety}} {{One source|date=July 2023}} [[File:Zircon-192914.jpg|thumb|Zircon (FOV {{nowrap|3.0 × 2.4 mm)}} from Mont Saint-Hilaire, Canada]] '''Jargoon''' or '''jargon''' (occasionally in old writings '''jargounce''' and '''jacounce''') is a name applied by gemologists to zircons that are of sufficient quality to be cut as gemstones, but not the red color that characterizes the ''hyacinth'' or jacinth. The word is related to Persian {{lang|fa|zargun}} (zircon; ''zar-gun'', "gold-like" or "as gold").<ref name="EB1911">{{EB1911|inline=y|wstitle=Jargoon|volume=15|page=276}}</ref>
Some of the finest jargoons are green, others brown and yellow, while some are colorless. The colorless jargoon may be obtained by heating certain colored stones. When zircon is heated it sometimes changes color, or loses it, and at the same time usually increases in density and brilliancy. The so-called ''Matura'' diamonds, formerly sent from Matara (or Matura) in Sri Lanka, were decolorized zircons.<ref name="EB1911"/>
The zircon has strong refractive power, and its lustre approaches adamantine, but it lacks the fire of diamond. The specific gravity of zircon is subject to variation in different varieties;{{Dubious|date=July 2021}} thus Sir A. H. Church{{verify inline|reason=check this is the correct person. Could be Arthur Harry Church but seems much less likely and it could be someone with no Wikipedia article|date=June 2024}} found the specific gravity of a fine leaf-green jargoon to be as low as 3.982, and that of a pure white jargoon as high as 4.705. Jargoon and tourmaline, when cut as gems, are sometimes mistaken for each other, but the specific gravity is distinctive, since tourmaline is only 3.103. Moreover, in tourmaline the dichroism is strongly marked, whereas in jargoon it is feeble. The refractive indices of jargoon are much higher than those of tourmaline.<ref name="EB1911"/>
== References == {{reflist}}
==Sources== *[http://www.farlang.com/gemstones/kunz_gems_and_precious_stones/page_120 Kunz: Gems and Precious stones of North America; Zircon]
==External links== *{{commons category-inline}}
{{EB1911 article with no significant updates}}
Category:Gemstones Category:Zirconium minerals
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