

^ 



JOURNAL 



OF THE 



Elisha Mitchell Scientific Society 



Volume XXXIV MARCH, 1919 No. 4 



IXDUSTEIAL ArPLICATIOXS OF ZIRCONIUM AXD ITS 



COMPOUNDS 



By F. p. Vexable 



PRECIOUS 



The earliest use made of a compoimd of zirconium 

 STONES was that of the natural silicate as a precious stone. 



It was known under the names zircon, jargon, and 

 hyacinth, and in early times was also supposed to have medicinal 

 value. The use of the name hyacinth among the ancients was con- 

 fusing as, besides the zircon, it sometimes meant the carbuncle and 

 also a dark amethyst. The zircon, kno^^^l by lapidaries commonly as 

 the Ceylon zircon or jargon, was regarded as distinct from the hya- 

 cinth and was usually colored fire-red, yellow, yellowish-green or 

 gray. The hyacinth was distinguished as oriental hyacinth. Its color 

 was deep red with a touch of brown or sometimes of orange red. Zir- 

 cons show a great variety of colors from colorless to red, brown, yel- 

 low, green, gray, white, pink, and blue, besides intermediate tints. 

 They may be translucent, but ordinarily are opaque. 



On account of its hardness (7.5) the zircon is cut with diaiiioiid 

 powder or emery. It is cut in the rose, table, or brilliant form. The 

 value depends chiefly upon the purity of the color. On account of its 

 lustre and hardness it has been substituted for the diamond. In<leed. 

 at one time it was supposed to be an inferior variety of diainoiul. It 

 has been used in jeweling watches and as suj)ports for the knife edges 



