“Not sure what to make of it , we shown it to many knife and axe people all said it has Marbles Pat. 3 slot (grooved) head mount, unmarked and early could have had the handle replaced. The slab side insert is also an old design. Many people wanted to know how much but no offers given and not sure if I would rather keep it. Good Luck if it is a marbles it is very rare, if not someone did a great job many years ago”