I found these cents with some others in my grandfather's collection and first thought that they'd been scraped in some kind of coin slot - my grandfather was a shopkeeper throughout his life. Then I read about the woody coins, which look quite similar, on the Canadian forum earlier and wondered if these would also be woody coins.
acloco: my grandfather didn't put his coins into display books - they're mostly in envelopes or loose in boxes. So I will have to photograph them as I come across them! These cents were in an envelope with a dozen others from the same era.
Although he apparently had many great dollar coins (marked in his coin guide), either he or someone later must have sold them, as I have found mostly cents, nickels and dimes. There's more variety in the Canadian and foreign coins.