Chem. Also TANTALIUM. [f. TANTAL-US, with the ending -um (more usually -ium), appropriate to metallic elements: cf. aluminum and aluminium; see quot. 1802.] One of the rare metals, occurring in combination in various rare minerals, and in certain metallic ores; discovered in 1802 by Ekeberg in two minerals, one from Finland and the other from Sweden, which he named tantalite and yttrotantalite. It has been isolated as a solid of greyish-white color and metallic luster, and is used (since 1906) for the incandescent filament in electric lamps. Atomic weight 182; symbol Ta. Also attrib., as tantalum lamp, etc.
[Cf. 1802. Ekeberg, in Kongl. Vetenskaps Acad. Handl., XXIII. 80 (tr.). This new recruit among the metals I call TANTALUM, partly following the custom which favours names from Mythology, partly in allusion to its incapacity, when immersed in acid, to absorb any and be saturated.]
1809. Wollaston, in Phil. Trans., XCIX. 246. The Swedish metal has retained the name of Tantalum given to it by M. Ekeberg.
1810. Henry, Elem. Chem. (1826), II. 69. The oxide of tantalum, ignited with charcoal, melts and agglutinates.
1906. Price Sheet. Siemens Tantalum Lamps for continuous current…. The Tantalum Lamp differs from the ordinary glow lamp in having a filament of the rare metal Tantalum instead of carbon.
1907. Outlook, 23 March, 378/1. Tantalum … is so hard and brittle that no ordinary metallurgical process was able to turn it into wire.
