Canada has used different proportions of silver in its coins.

The alloy was 92.5% silver, 7.5% copper from 1858 to 1919. From 1920 to 1968 the composition was 80% silver, 20% copper, which let Canada continue producing silver coins for a couple of years longer than the U.S. where the alloy was a more expensive 90%/10%.

By 1968 the rise in silver prices caught up with Canada too. In mid-year the composition was changed to 50% each, but by the end of the year even that was too costly to make coins so it was replaced with pure nickel.

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