Tellurium

(těl-lū're-um.) [From L. tellus, the earth.] (Min.) An element belonging to the sulphur group, and approaching in character a metal. It was discovered by Klaproth in 1798; physically it strongly resembles the metals; it is tin-white, shining and metallic-looking, crystallizing readily, and very brittle. It is a bad conductor of heat and electricity. Sp. gr., 6-3; at. weight, 128; Symbol, Te. It melts at 9320, and at a higher temperature volatilizes. When heated in the air it takes fire with a blue flame. In its chemical properties it strongly resembles sulphur and selenium; like them it CLA P R H 0 ぴ Fig. 627. forms two oxides, tellurous acid (TeO2), and telluric acid (TeO3), which unite with bases, and form salts which are analogous to the corresponding salt containing sulphur and selenium. [s. 883]