Philadelphia Paper - The Cause of Rustiness and of some of the Losses in Working Gold

There has alrvays been atheory among those working placer mines that gold is both folind rusty," and becomes so under treatment, hy which they nleun, not that gold becomes coated with oxide: of gold, but that it, is either coated superficially or alloyed with some substsnee which prevents the contact with mercury,and thus precludenthe possibility of amtrlgamation. To such aoiiditions of the