Watch List notes:

Potosi, Bolivia, cob 8 reales, 1650 O, with crowned-PH (Mastalir PHb-ao) countermark on shield, rare, Mastalir Plate. S-P35; KM-19b; Cal-1488. 19.99 grams. Broad flan with well-detailed full shield and cross despite thinning from corrosion (also darkly toned), both assayers visible, full crown and most of king's name and ordinal, clear date at 12 o'clock with modern 5 and dots between digits, distinctively tall crown in countermark (the PH itself not visible). Pedigreed to the Roberto Mastalir Collection of Countermarked Potosi Cobs, Plate Coin (page 364 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 photo-certificate. From: Capitana, sunk in 1654 off Chanduy, Ecuador
($300-450)