Employees at the armored car companies, I have been told, regularly scan the coins being sorted in hopes of finding silver dimes, half-dollars, and quarters. They pull those relics (of a better, vanished time) out of circulation.
One could walk into any bank, ask for as many rolls of half dollars as you can afford and pay face value. Then spend the evening looking at the edges and dates of the coins. Out of $1,000 one may find a silver piece or two.
Silver coins can be easily sorted from clad coins by automated machinery ... The silver coins and the clad coins make different sounds when dropping through a coin op mechanism... I found silver in the “reject” bin at one of those automated coin sorter machines they place in banks and some retail stores... falls right through even though they are the same dimensions.