Watch List notes:

Pair of gilt-bronze uniface proof patterns (obverse and reverse essais) for Medellin, Colombia, gold 20 pesos, 1873, engraver A. Barre (Paris), rare, NGC PF 64 (both, one slab).Restrepo-78 (p. 207); Sed-45; KM-TS11, TS12. Bright gold surfaces with strong luster, light marks and rim-bumps for the grade but desirable as a nicely matched pair slabbed together, from a well-known series of trials by engraver Albert Barre, of which the 20 pesos was never adopted at the Medellin mint.
($5000-7500)