4 Reales - Carlos III

Carlos III's monetary reforms of 1772 mandated the transition from cob ("macuquina") coinage to the milled portrait coinage across Spanish colonial mints, and Guatemala's Casa de Moneda was among the last to comply. The 1772 date marks the first year of this new type at the Guatemalan mint — a facility that had been striking cobs for over two centuries and required substantial retooling to produce the precision edge-lettered flans the new standard demanded.

Guatemala's output for this series remained modest relative to Mexico City or Lima, and attrition from the region's active trade circuits has kept surviving examples in collectible grades genuinely scarce. The series closes in 1785, when Carlos III's further reforms rationalized colonial mint operations.