Mexico
Carlos & Johanna Cob 4 Reales ND (1541) oMo-oPo XF45 NGC, Mexico City mint, KM17. Plain circles type. Deeply toned and fairly sharply struck for issue, with some scattered roughness. A pleasing example of this error type, featuring the G in REG punched over an X.
Ex. 'Golden Fleece wreck' Research Collection (Sedwick 4, November 2008, Lot 187)
Estimate: 1500-2000 USD