This is a gun that came down to me in the family. My Mom believes that this was my Great Great Grandfather's and that he used it for hunting after the US Civil War (i.e. post 1865). He in turn passed it on to his son, my Mom's father, my Grandfather. I never had a chance to discuss it with him before he passed on, back in the late eighties. The only identification I find on it are the words "LONDON TWIST" on top between the barrels and a collection of proofs, a few on the sides of the barrel and a batch underneath the barrel when it is taken off the stock. I have taken several photos that I hope will help...most all are close ups thinking this would help. If there is anything else you would like to see I can get a photo of it and post. If there is anything else I should inspect and/or describe I would be glad to. I would like to know approximately where and when, and by whom, it was manufactured and what is it's approximate worth? Thanks in advance for your help.