You are talking about a church key can opener there Colin. I still use them
Used to have something with a similar style head but a horn handle. It was for putting a brace of holes in the top of tins of say evaporated milk. One as a pouring hole the other as an air vent. The two little bottle opener type indents caught on the lip of the tin and the point pushed through.
Don't know if that's what it is but it looks awful like it.
Sent via smoke-signal from a woodland in Scotland.
Aye, hadn't really thought about it that way as Church Keys were always lighter and more pocketable where as this was a big-ish double ended thing with a big lump of polished curved horn atween them. It was more of a table piece. Come to think of it I've not really seen one like it Hugh. It was mainly used for poking holes in Carnation® Evaporated Milk tins.
Sent via smoke-signal from a woodland in Scotland.