It is a .52 percussion breechloader with the Sharps patent pellet primer mounted in the lockplate. The saddle ring bar is the long type, 9".
The key feature which differentiates the '52 from the '53 is the retaining spring on the right side of the foreend which secures the lever hinge pin.
There is no finish left on the metal work but no rust is evident. The stock has taken a few knocks and there is an old crack near the risk but seems solid.
An interesting feature is the marking on the but plate. It would appear to be Arabic numbers, 1 over 36 -any help with that would be greatly appreciated!