Watch List notes:

Potosi, Bolivia, cob 8 reales, 1650 O, with crude-arms (Mastalir CL) countermark on cross, very rare, Mastalir Plate. S-P35; KM-19b; Cal-1488. 17.89 grams. Unusual and very rare countermark (only four known) consisting of crude lions and castles without a border, supposedly a local imitation or emergency issue (per Mastalir), the bottom half of which is bold on this coin in the center of the cross, that side also with bold full 50 of date (Spanish 5) in a heavier, earlier style uniquely muled with a later, finer-style obverse (one known), with full shield and much legend, thin from corrosion but still well detailed and with contrasting toning in crevices. Pedigreed to the Roberto Mastalir Collection of Countermarked Potosi Cobs, Plate Coin (page 109 in Part A and page 394 in Part B) in his book The Great Transition at the Potosi Mint, 1649-1653, The 1649-1652 Crowned Shield Coinage and the Countermarks of 1652 (2021), with original Herman Moro certificate. From: Capitana, sunk in 1654 off Chanduy, Ecuador
($300-450)