What might this be, and what was it used for?
Millions must have been made, this is not anything special at all, but I wonder how many of you have seen one.
If it helps, the letters on the back, here on the left, are C.O.3. underlined by an arrow, pointing to the right; on the front (right), and I know it is very difficult to see, is a crest, and it is a far from unknown one at that.
What do you reckon?