8 Reales - Carlos IV Numeral IIII, Carlos III portrait

This transitional issue carries the portrait of Carlos III on the obverse despite being struck in 1790, the year after his death — a direct consequence of the lag between Madrid's orders reaching colonial mints and new dies being prepared and shipped across the Atlantic. Carlos IV had already ascended the throne, hence the IIII numeral, but the physical dies bearing his father's likeness remained in use at Mexico City until the new portrait type could be introduced. The overlap produced a distinct one-year type that collectors have catalogued separately ever since.