Mexico City, Mexico, 4 reales, Charles-Joanna, "Late Series," assayer A to right, mintmark M to left (M-A), encapsulated NGC XF 45. Nesmith-58 type; CT-79; S-M6. 12.6 grams. Broad flan with full details, deeply toned, hint of surface corrosion. From the "Golden Fleece" wreck (ca. 1550). (Estimate: $400 - 600)