Silver all but vanished from U.S. coinage in 1965. Prior to then, U.S. dimes, quarters and fifty cent pieces were made of 90% silver.
After 1964, only Kennedy half dollars contained any silver at all (though it was reduced to 40%). These coins were minted until 1970, when they too were converted to copper clad with nickel.
In the late ‘70s, I spent several years working in the grocery business in Alaska. In 1977, silver was getting ready to make its big move from the low single digits up to a bull market blow off price of around $50. Having read Harry Browne’s book titled “How you can Profit from the Coming Devaluation,” as well as the writings of his former boss, the late Jerome Smith, I was fully “on board” with this developing story.
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