25 Colones 2nd coat of arms, non-magnetic, segmented edge

Costa Rica's bimetallic and multi-alloy coinage underwent a quiet but deliberate overhaul in the early 2000s as the Banco Central responded to counterfeiting pressures and vending machine compatibility requirements across the Central American region. The shift to a non-magnetic copper-aluminium-nickel alloy distinguished this issue from its predecessor and complicated clandestine duplication considerably. The segmented edge — alternating plain and reeded sections — was an additional security measure borrowed from European practice, most visibly the euro's rollout a year earlier.

KM#229a separates from the magnetic 229 primarily by alloy composition, a distinction that sorting machines register instantly but the naked eye cannot.