Dear Ron,

Thank you for contacting Mearto with your appraisal inquiry. My sincere apologies for the delay with the apprisal.

The presented object appears to be a prototype for a handle of a derringer type gun or a model for the production. There were derringer type pistols with all-metal grips and this piece could be used as an idol in the production process. Sadly the date of the patents doesn't lead to an identification of the type. This piece was probably made in the USA and the renewed patent is dated with 1877 or shortly later.
This piece is in good condition and there is no serious damage visible in the images provided.
A fair market estimation would be between 50 to 100 USD.
This estimate is based on actual recent past recorded auction sales of comparable items. Retail "asking prices" can be higher and may vary.

With kind regards,
Georg