A base metal usually obtained by mixing silver and copper.

The designation is now generally applied to any coin ostensibly called silver, but containing in reality more than fifty per cent of copper. If the proportion of cop- per is more than seventy-five per cent, the composition is called black billon, argen- tum nigrum, or moneta argentosa . Lastly, if the coin is of copper, and is only thinly washed with silver, as in the case of some of the Scheidemiunzen (q.v.) it is called Weisskupfer , i.e., white copper. See Potin. The Encyclopaedia Britannica in an early edition of 1797 states that gold under twelve carats fine is called billon of gold.

Ruding (i. 210) mentions the Turonenses nigri , that is, the black money of Tours, which was brought to England in the four- teenth century and prohibited.