USA (New Orleans mint), $20 coronet Liberty, 1853-O, ex-"Fort Capron treasure." KM-74.1. 33.40 grams. UNC details, saltwater surfaces, nice gleaming color, underlying luster, very minor marks, popular branch-mint issue. From the "Fort Capron treasure" of 1857 (AKA "Gordy-Ashley gold").
Estimate: $4000 - 6000