My guess: Wax, wooden, or cork plates plugged into each side via the large holes. On the the replaceable plates were some sort of painted or engraved label, i

My guess: Wax, wooden, or cork plates plugged into each side via the large holes. On the the replaceable plates were some sort of painted or engraved label, indicating something such as: - a dice or other game piece - a fortune or God (some other mythical image) - some other game of chance type option