Jim, no wonder its in a safe deposit box! With that kind of history and provenence, the value would be way up there. It appears to be, and the time would fit, to be a regular first generation (black powder) model. It is very likely to be .45 Colt. It was probably blued with a case hardened frame. The firing pin would be on the hammer nose. Thus the carrying with an empty cylinder under the hammer. When Colt was still in business, you could have got a letter from them with date of manufacture, finish, calliber, where shipped, etc. I don't know if anyone is still doing this. If you write to Guns of the Old West, a quarterly magazine devoted to guns of this type, someone will know something to help you more than I can. Good luck. Stan