针碲金银矿

[ noun ]
a silver-white mineral consisting of silver gold telluride; a source of gold in Australia and America
<noun.substance>

Sylvanite \Syl"van*ite\, n. [Fr. Transylvania, where first
found.] (Min.)
A telluride of gold and silver, {(Au, Ag)Te2}, of a steel
gray, silver white, or brass yellow. It often occurs in
implanted crystals resembling written characters, and hence
is called {graphic tellurium}. H., 1.5-2. Sp.gr., 7.9-8.3.
[Webster 1913 Suppl.]