I know this might post date the Old West by a few decades but I think some of you might be interested in knowing about it as it happened just 20 years after Arizona became a state in 1912- it took them that long to convince Washington that most the outlaws had been tamed, jailed or run out of the territory. Thus for your further consideration.......
In 1932 the state of Arizona issued vehicle license plates made of Copper. They did this for a number of reasons including to boost the demand for Copper which in turn would help put miners back to work during the great depression. The Arizona Highway Commission also urged other states to consider using the "Red Metal" to help alleviate the over supply of Copper (so the miners could get to digging again?).
Thus in 1932 70,000 pounds of Copper was used in the manufacture of the Copper license plates at the tune of 14 and 3/4 cents a piece. The state went on to stamp Copper plates through 1934.
Bet they are worth a bunch more than a pretty penny today. Happy prospecting to Henry Moon and you other prospectors out there. I wonder how many are buried in the desert sand or hanging on a ranch wall out there myself.