Potosi, Bolivia, cob 1/2 real, 1673. S-P37b; KM-22; Cal-163. 1.31 grams. Slightly corroded yet with two clear dates, full monogram, and partial king's name in legend, grayish silver patina. With original ROBCAR photo-certificate #M007288. From: Consolacion, sunk in 1681 off Santa Clara Island, Ecuador
($60-90)