25 Sen

Indonesia's early aluminum coinage of the mid-1950s was issued against a backdrop of severe fiscal strain — the new republic was still absorbing the debt obligations imposed by the Dutch as a condition of the 1949 sovereignty transfer, a financial burden that constrained monetary policy for years. Aluminum was chosen partly on cost grounds, as copper-nickel alloys were beyond practical budget at the time.

The series ran across three years, with KM#11 representing one of the first domestically authorized coin types issued under Bank Indonesia following its formal establishment in 1953.