^Lot 188 Potosi, Bolivia, cob 8 reales, 1650 O, modern 5, with crowned-F (Mastalir Fa1) countermark on shield

Potosi, Bolivia, cob 8 reales, 1650 O, modern 5, with crowned-F (Mastalir Fa1) countermark on shield, rare, Mastalir Plate. S-P35; KM-19b; Cal-1488. 23.63 grams. Broad flan (thin from light corrosion) with full shield and cross, much legend and exceptional full crown, all in a fine style more typical of Royals (galanos), nearly full date with modern 5 but no dots between the digits (unique thus), just the crown of the countermark visible (but fully), nice toning, hairline edge-split. Pedigreed to the Roberto Mastalir Collection of Countermarked Potosi Cobs, Plate Coin (page 108 in Part A and page 325 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. Recovered from: Capitana, sunk in 1654 off Chanduy, Ecuador