Salting a mine was a popular scam during the gold rush. Scammers would plant a precious gem or gold ore in a mine or on the landscape to convince others into purchasing shares in a worthless or non-existent mining company.
They would do this to give the appearance that the land or mine was rich in natural minerals. Some of the more famous salting mine scams included the Diamond Hoax of 1872 and the Bre-X gold fraud of the mid-1990s.