tellurium science definition

A metalloid element that occurs as either a brittle, shiny, silvery-white crystal or a gray or brown powder. Small amounts of tellurium are used to improve the alloys of various metals. Atomic number 52; atomic weight 127.60; melting point 449.5°C; boiling point 989.8°C; specific gravity 6.24; valence 2, 4, 6. See Periodic Table.