The Collaborative International Dictionary
black tellurium
Tellurium \Tel*lu"ri*um\, n. [NL., from L. tellus, -uris, the earth.] (Chem.) A rare nonmetallic element, analogous to sulphur and selenium, occasionally found native as a substance of a silver-white metallic luster, but usually combined with metals, as with gold and silver in the mineral sylvanite, with mercury in Coloradoite, etc. Symbol Te. Atomic weight 125.2.
Graphic tellurium. (Min.) See Sylvanite.
Tellurium glance (Min.), nagyagite; -- called also black tellurium.