old 10 gauge reloading block

I have a reloading block made of walnut and its for a 10 gauge. It has a pat. date of dec 11 88 (1888) It would be used to load 10 gauge shells. It also says PACK'S PERFECT by the pat. date. It has 3 peices of wood with a hinged top. There are holes drilled through the 3 peices of wood. The holes go from top to bottom. On the hinged to there are counter sunk holes where the brass part of a shotgun shell would sit.on the bottom side of the vertical wood peices it is flared out so you can dump powder/shot in. I was wondering if anyone knew anything about this or how much its worth.