Nevada, being a big silver producing state, had required by law at one time many decades ago that the casinos use U.S. silver dollars.

If we learn from history ... when silver "shot up" past $1.29 per ounce back in the 60's and early 70's, U.S. silver dollars contained more than $1.29 worth of silver ... which caused the silver dollar to "disappear" by the $1000 bagfulls from Nevada casinos and the state law was changed to permit the striking of privately issued tokens ... primarily Franklin Mint tokens.

Not only Nevada's casinos were affected, but U.S. silver coinage was affected as well for everyday commerce in the country. Hoarding of 90% (.900 fine) silver dimes, quarters and half dollars struck before 1964 created the need for 40% clad silver coins in 1965-1969... and even they became worth more in melt value than face value as silver prices shot up to close to $50 per ounce in 1980 as a result of silver price speculation and manipulation by the Hunt Brothers of Texas.

Will we see a repeat of that scenario. I doubt it, but at today's rising prices it becomes cost effective to mine silver once again.