Description: San Luis Potosi, Mexico. 500 Pesos, P-S404p M489p, Miners at right, arms at left, Printed on india paper on large cards, the Front is PMG graded Gem Uncirculated 66 EPQ and the back is Gem Uncirculated 65 EPQ. ABNC. This is the only example graded in the PMG census as well as the highest graded note that will be difficult to improve upon.