Watch List notes:

Potosi, Bolivia, cob 8 reales, 1650 O, with crowned-F (Mastalir Fa2-x) countermark on cross, rare, Mastalir Plate. S-P35; KM-19b; Cal-1488. 21.16 grams. Good full cross with full 650 of date at top (modern 5, variety with cross-of-four-dots flanking the date, not visible on this one), full but corroded shield (fine style), clear countermark on cross (normally seen on shield), edge-crack, toned. Pedigreed to the Roberto Mastalir Collection of Countermarked Potosi Cobs, Plate Coin (page 342 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)