[a fool in paradise]

At what point was the oil and grease deliberately ruining the currency?

https://www.livescience.com/34286-legal-or-illegal-to-destroy-coins-paper-money.html

According to Title 18, Chapter 17 of the U.S. Code, which sets out crimes related to coins and currency, anyone who “alters, defaces, mutilates, impairs, diminishes, falsifies, scales, or lightens” coins can face fines or prison time.

[real saxophonist]

Every year (except the last couple), the steam locomotive Union Pacific 844 comes through town, taking people up to Cheyenne Frontier Days.

Kids always put coins on the tracks.

[Flash Bazbeaux]

The pennies they make nowadays, which are mostly zinc, are easily destroyed. Even a little salt will corrode them.