salting the mine

Verb

salt the mine (third-person singular simple present salts the mine, present participle salting the mine, simple past and past participle salted the mine)

1. Used other than figuratively or idiomatically: see salt, the, mine.
   • He then discovered that Lovell had salted the mine with ore from the Little Pittsburgh.1989, John Burke, The Legend of Baby Doe: The Life and Times of the Silver Queen of the West, U of Nebraska Press, →ISBN, page 53
2. (broadly) To set up a confidence trick; to plant false evidence of the value of something.
   • "Yes. I thought it would be a shrewd move to salt the mine." I didn't get this. She seemed to me an aunt who was talking in riddles.1954, P.G. Wodehouse, Bertie Wooster Sees It Through, Simon and Schuster, →ISBN, page 86