Watch List notes:

Potosi, Bolivia, cob 4 reales, 1737 M, NGC AU 58, finest and only example in NGC census. S-P47; KM-30a; Cal-1192. 13.24 grams. Very chunky flan with crude edge (as made) but with very sharp details and lustrous surfaces indicative of its exceptional grade, with clear date and mintmarks but assayer quite weak (could be E instead).
($300-450)