Canada decided to stop coining currency in silver and switch to pure fiat using nickel after 1967, some 1968 50% silver 10 cents and 25 cents being the exception. The US did the same after 1964 with exception to halves up to 1970. In fact all countries de-silvered their coinage in the late 60s. Coincidence? I don't think so. Coordinated? Yes. Setting the stage for revoking the Bretton Woods a few years later. Just don't get me started on the huge profits the government makes in Seniorage.
The 1968 Nickel metal Voyager dollar is the first year until it ended in 1986 when the much smaller bronze Loon Dollar came in 1987.
The Nickel Voyager, right, is 2mm smaller in diameter also a little thinner than the silver Voyager on the left. Silver coins have a distinct ring when struck with another coin.
Wow, thank you very much for this detailed answer!
I knew I was right asking you!
!PIZZA
deep silver know-how! :)