Auer von Welsbach, Carl Freiherr

Auer von Welsbach, Baron Carl, b. Vienna, Sept. 1, 1858, d. Welsbach Castle (municipality of Mölbing, Carinthia), Aug. 4, 1929, chemist; son of Alois Auer von Welsbach. A. was the first to isolate the didymium elements neodymium and praseodymium, both of the rare earth group. He found that a fabric impregnated with a mixture of thorium nitrate and cerium nitrate could be made into a mantle that glowed brightly when heated by a gas flame. Patented in 1891, the Welsbach mantle ("Auer Glühstrumpf") greatly improved gas lighting. His highly successful gaslights were produced in Atzgersdorf (then in Lower Austria, today part of Vienna's 23rd district). Later on, A. introduced the first metallic filament for incandescent lamps by using osmium and tungsten which paved the way for the modern light bulb. In addition, A. also developed misch metal, a mixture of cerium and other rare earths, which he combined with iron to make Auer's metal, to make sparks used in lighters. For processing thorium and cerium he established the Treibach Chemical Works (Treibacher Industrie AG) in 1898.

Literature: F. Sedlacek, A. v. W., 1934; Treibacher Chem. Werke, 1980; H. Auer-Welsbach, Die Erfindungen des Dr. C. A. v. W., master's thesis, Graz 1992; NDB; NÖB; ÖBL.