Tellurium (Te), semimetallic chemical element in the oxygen group (Group 16 [VIa] of the periodic table), closely allied with the element selenium in chemical and physical properties. Tellurium is a silvery white element with properties intermediate between those of metals and nonmetals; it makes up approximately one part per billion of Earth’s crust. Like selenium, it is less often found uncombined than as compounds of metals such as copper, lead, silver, or gold and is obtained chiefly as a by-product of the refining of copper or lead. Continue reading from Encyclopedia Britannica
Tellurium was discovered in 1783 by Franz Joseph Müller von Reichenstein at Sibiu, Romania. He became intrigued by ore from a mine near Zalatna which had a metallic sheen and which he suspected was native antimony or bismuth. (It was actually gold telluride, AuTe2.) Preliminary investigation showed neither antimony nor bismuth to be present. For three years Müller researched the ore and proved it contained a new element. He published his findings in an obscure journal and it went largely unnoticed.
In 1796, he sent a sample to Martin Klaproth in Berlin who confirmed him findings. Klaproth produced a pure sample and decided to call it tellurium. Rather strangely, this was not the first sample of tellurium to pass through his hands. In 1789, he had been sent some by a Hungarian scientist, Paul Kitaibel who had independently discovered it. Continue reading from The Royal Society of Chemistry
Tellurium is often used to improve the machinability of copper and stainless steel. It’s used to make blasting caps, added to cast iron and used in ceramics. Adding tellurium to lead improves the strength and hardness of the metal and decreases corrosion. Tellurium is usually found as calaverite, the telluride of gold, and also combined with other metals. It is found commercially in electrolytic refining of blister copper from anode muds during the process. Continue reading from LiveScience
