1 Quattrino - Carlo II

Carlo II of Spain held the Duchy of Milan as a Crown possession throughout his reign, but the duchy retained its own mint and coinage system under local governors. Carlo himself — intellectually disabled, epileptic, and the product of generations of Habsburg inbreeding — was functionally incapable of governing, leaving Milan administered by a succession of Spanish-appointed regents. The quattrino was the lowest practical copper denomination in Milanese circulation, struck in large quantities precisely because the working poor had little use for silver.

The CNI attribution places this among a well-documented run, though die workmanship on copper issues of this period is notoriously inconsistent across the long date range.