Watch List notes:

Mexico City, Mexico, 4 reales, Charles-Joanna, "Late Series," assayer A to left, mintmark M to right (A-M). Nesmith-62a; Cal-132; S-M6. 13.50 grams. Choice full details (AU), including legends, with nice toning all over, the shield side with dark "horn silver" on surface, otherwise uncorroded. Recovered from: "Golden Fleece wreck," sunk ca. 1550 in the northern Caribbean
($500-$750)