HE Zircon is a lovely stone, the red and brown varieties being especially noteworthy. Some of the finest Jargoons present yellow, green, and blue tints, not unlike those of the Tourmaline, but with much more fire and lustre. Some specimens when submitted to great heat, increase in lustre, but at same time lose colour.
The Zircon is distinguished when in its natural form, by its quadrilateral crystals, terminating at both ends in a pyramid. It is of adamantine lustre, transparent to sub-translucent. In former times this gem was more highly valued than at present.
Although the localities which yield Zircons fit for working into ornamental stones are but few, it should be borne in mind that the coarser forms of Zircon are present in a great variety of rocks, such as the Zircon-syenite of Norway and Siberia.
Nicols writing of Zircons 230 years ago, says— "They are found in Ethiopia, India, and Arabia. The Arabs distinguish three kinds—1, Rubri Coloris : 2, Citrini Coloris : 3, Antimonii Coloris. Of these the worst is found in the river Iser, which is upon the confines of Silesia and Bohemia."
Klaproth in 1789 discovered in the Zircon an earthy basis, to which he gave the name of Zirconia. It is the