Watch List notes:

Mexico City, Mexico, 4 reales, Philip II, assayer F/O below mintmark oM to left, denomination oIIII to right, very rare.S-M12; KM-unl (36 for type); Cal-unl (Type 158).13.68 grams.Very broad flan with some peripheral flatness but nearly full crown in addition to choice interiors (shield and cross), the oMF/O clear but weak (first we have seen or heard of), XF.
($200-300)