This is a restrike made outside the mint from dies sold as scrap possibly by Joseph J. Mickley or Montroville Dickeson.
It was made using the 1818 Browning 2 quarter obverse and the 1818 Newcomb 8 cent reverse. The dies appear worn and rusted but this could be the result of the overstrike. According to Pollock an 1860 quarter was used as a planchet, its reeded edge crushed.
The piece is unique and has a pedigree dating back into numismatic antiquity. It is ex Cogan 3/1862, Seavey, Parmelee, Woodin, Brenner, T.J. Clarke, J. Welch, 72 ANA, Bowers and Ruddy Rare Coin Reviews, Bowers and Ruddy 6/82, Stacks 3/85, Queller-Heritage 1/09.
Photo courtesy of Heritage.