"junk silver" especially dollar coins and half dollars are some of my favorite silver to stack. Canadian silver primarily, but the odd time I can buy a Morgan dollar, or peace dollar I usually do for the right price!

Canadian pre 1921 quarters, 5c, dimes, and half dollars were on the British sterling standard, and therefore 92.5%. after that until 1967 dimes quarters and halves and dollars, were 80%, 1968 some became 0% silver while some were still 50%. There were still silver dollars, but not circulation after 1868. That's Canadian silver coins as best as I know.