Thank you for submitting your item for appraisal. This appears to be a vintage american guitar, manufactured by C.F. Martin & Company, Nazareth. Condition appears to be good within the usual range of used instruments. The mirrored veneer on the back might be rare brazilian rosewood / dalbergia nigra. If this is confirmed by microscopic analysis of the wood grain you will need a CITES to be able to sell it. The estimate is based on similar guitars offered or sold at auction. The good provenance might add some extra value to the high estimate.