At a local auction there is a Field & Staff Officers presentation sword without scabbard. The swords blade is tarnished but the etching is all visible. On one side of the blade is ‘US’ on the other an eagle with ‘E Pluribus Unum’ with other etchings. The blade at the hilt is impressed with an individual ‘R’ and a ‘D’ with no maker identified. The hilt on the blade side is impressed ‘FBD’ and has an emblem of a sword through a bell shaped object with a crown. Do you recognize the markings and would you be able to assist me in determining a fair auction value as I will be bidding on this for resale.