[a. F. jargon (1762 in Dict. Acad.), ad. It. giargone (Hatz.-Darm.). Ulterior derivation obscure: Hatz.-Darm. compare OF. jagonce, jargunce (in St. Brandan), variants of jacinth (see JACOUNCE); but most etymologists identify it ultimately with ZIRCON, Pg. zarcão, Arab. zarqūn. (Both the hyacinth or jacinth and the jargon are varieties of zircon.)]
A translucent, colorless or smoky variety of the mineral zircon, found in Ceylon.
α. 1769. Pub. Advertiser, 29 May, 3/4. Rough and polished Emeralds … Topazes, Jargoons.
1825. Hone, Every-day Bk., I. 1526. These borders are studded with … jargoon diamonds.
1883. A. H. Church, Prec. Stones, iv. 28. The diamond and the jargoon do not improve or bring out each other’s qualities, for they have too many points in common.
1884. F. J. Britten, Watch & Clockm., 215. The Zircon, the Hyacinth, and the Jargoon are silicates of zirconia.
β. 1797. Monthly Mag., III. 206. The hyacinth … consists … more than six-tenths of its weight of a peculiar earth, now known under the name of jargon, zircon, or circonia.
1868–72. Watts, Dict. Chem., V. 1079. The name hyacinth includes the bright-coloured varieties of zircon;… the greyish or brownish kinds are called zirconite. A variety from Ceylon, which is colourless, or has only a smoky tinge, and is therefore sold for inferior diamonds, is sometimes called jargon.
