PCGS 1969 Canada dollar transitional off-metal struck on a silver half dollar planchet from 1967. The coin is silver, and is the weight of a Canada half dollar. 

Canada stopped minting silver 50c in 1967, and this coin is a 1969. A leftover 1967 silver half dollar planchet somehow made it into a press striking 1969 dollars and was struck creating a transitional off-metal. 

Extremely rare, with this being the only example known to us. 

PL65 with white mirrored fields and just a hint of toning.