Watch List notes:

Mexico City, Mexico, cob 4 reales, (16)23D, rare. S-M18a; KM-38; CT-692. 13.19 grams. Bold full oMD in tiny characters, full 23 of date with 2 backwards (made from a rotated N) and 3 like a 4 with a curved tail, nearly full shield and cross but peripherally flat, no corrosion. "Lucayan Beach wreck," sunk ca. 1628 off Grand Bahama Island

Estimate: $250-375