About SemiPrecious Stones: Zircons or Matura Diamonds

ZIRCON is alphabetically the omega of the semi-precious stones occasionally used, but, as it is probably used much more than any other mineral in this category, it is almost entitled to a chapter of its own. High specific gravity and an adamantine lustre are two marked characteristics of this mineral. Zircons are called "Matura diamonds," because of their abundance at Matura, Ceylon. Colourless or smoky zircons are called jargons or jargoons. Transparent zircons of a brownish, red-orange colour are called hyacinth or jacinth. Zircon is the heaviest gem mineral--more than four times the weight of water--its specific gravity being 4.2 to 4.86. Its hardness is 7 1/2. So high is its index of refraction--1.92--that it approaches the diamond in brilliancy when cut. Zircons of gem quality come mostly from Ceylon, where they are found in the form of rolled pebbles. Zircon is found in various American localities, but it is opaque.