This is a rare London proofed and shipped Richards conversion revolver complete with a Colt London Agency case with a cleaning rod, James Dixon & Sons oiler, L-shaped combination tool, and large cartridge block for ammunition (ammunition pictured for artistic purposes, not included). At the time of publication, according to Bruce McDowell in "A Study of Colt Conversions..." on pages 188-189, experts "could only account for two authentic casings of Von Oppen marked 1860 Richards conversions. Both are in private collections, and in typical London-marked oak cases with cartridge boxes." A case matching the present example is shown. This revolver has Von Oppen's mark on the trigger guard. Baron Friedrich Von Oppen was married to Colt's alleged former mistress and sister-in-law and served as his agent in Europe and as a manager of Colt's London Agency. Approximately 9,000 Richards conversion Model 1860 Army revolvers were manufactured circa 1871-1878 based on designs patented by Charles Brinckerhoff Richards (1835-1919) on July 25th, 1871. Very few of them appear to have "crossed the pond" to the United Kingdom, but they are believed to have seen significant use in the Old West. Richards was also one of the main designers of the Colt Single Action Army which was manufactured alongside the Richards conversions. The top of the barrel is roll-stamped "-ADDRESS COL. SAML COLT NEW-YORK U.S. AMERICA-" in one line. The percussion era style "COLTS/PATENT" marking is on the left side of the frame while some examples have the 1871 and 1872 patent marking. The cylinder has the classic naval battle roll scene. The barrel has a blade front sight, and a notch rear sight is on the breech plate. Matching serial numbers are visible on the cylinder, barrel, frame, trigger guard, and back strap. The assembly number "4556" is on the loading gate. The barrel, cylinder, and back strap are finished in blue. The frame, recoil shield, loading gate, and hammer are brilliantly casehardened. The trigger guard is silver plated and has the Rampant Colt trademark on the right and "44 CAL" on the left, and the grip is varnished walnut.