Potosi, Bolivia, cob 4 reales, (1649-50)O, with crowned-L countermark on cross. S-P35; KM-17b. 13.64 grams. Thick flan with crack and traces of corrosion in edge, full shield and cross, the latter with 100% full (and larger than normal) countermark, nicely toned with copper color on shield. From the Maravillas Research Collection of Countermarked Potosi Cobs, with Marex certificate and tag #0416. Recovered from: Maravillas, sunk in 1656 off Grand Bahama Island ($300-450)