This is a 2 piece cast iron melting pot (?) device. Appears to have a oblong opening in the front, which I believe is for inserting small pieces of coal for heat, with a round opening in the rear which I think is for exhaust. It is 12" tall, with both items attached, and the bottom pot is 12" wide. There are rings attached to both the upper and the lower pots, which I think is to allow for moving the pots while heated. There are not any markings on the bottoms, or any other areas.
Although I am guessing that this is some form of melting pot, the top pot has a closed top (approx. 4" across) vs pouring type of top. Both the top and bottom pots are clean without any residue to suggest prior use.