RARE METAL.

Waikato Times, Volume 116, Issue 19457, 22 December 1934, Page 4

RARE METAL.

QUALITIES OF INDIUM. Indiym, the rare metal with which scientists are just becoming acquainted, was so named because its -discoverers found that it produced indigo blue lines in the spectrum. It seems odd that a substance so historically associated with the colour blue should find a new and promising use in colo.uring glass yellow. . Mr William S. Murray, of Utica, New York, who is devoting himself to the study of this little-known element, in an effort to find commercial uses for its unique properties, has found that indium sesquioxide imports a beautiful yellow colour to glass, ranging from light canary to dark tangerineorangp, depending upon the amount of indi-um used. Heretofore the production of yellow glass has depended on compounds of uranium, cerium, and titanium. The uranium hydrate has a -greater colouring power than any of the usual compounds. Cerium and titanium have been used together in rather substantial amounts, but the colour Is lighter than is desired. Uranium gives a canary yellow colour. So far as has been determined, indium sesquioxide gives a more intense yellow colour than any of the other oxides used. One half-pound imparts a beautif-ul yellow to 10001 b of grassforming materials. This amount is about one-seventh that of'the metallic oxides previously used for colouring -glass yellow.