Looks a bit over built for a can crusher, but it appears whatever it crushes it does it in a full stroke as there doesn't appear to be a provision for it to short stroke. Not sure about ore but it seems like it could be hard enough to stop the machine possibly.
Agree with stamp mill.
Here's a grim story of the copper mining industry in northern Michigan that used such machines to separate the copper from the base material.
Even though that use ceased in the 1930's the stamp sands remain today. http://www.geo.mtu.edu/KeweenawGeoheritage/Lake/Gay_Sands.html
I originally thought can crusher was a far out answer but after looking at it again I don't think it's that far out. I suppose if you ran a recycling plant you would have a use for something like this...