Banknotes
Bank Indonesia notes were printed by Indonesian printer P.N. Pertejetakan Kebajoran dated "1960" with the overprint 'Riau' in denominations of 5, 10 and 100 rupiah, all carrying the image of President Soekarno but with colour and other design differences. Lower denomination notes, under Indonesian (and previously Netherlands Indies) law were the issuing privilege of the Indonesian government, and for Riau bore the date "1961" with the overprint "Riau", in 1 and 2 ½ rupiah denominations.
Identical notes, but for the overprint, were used for the West Irian rupiah in 1964. The five notes issued in Riau, the 5, 10, and 100 rupiah notes, minus the "Riau" overprint, plus the 1 and 2½ rupiah note designs, redated "1964", were then also used as Indonesian rupiah notes in 1965.
Green (1) and blue (2½) variants of the 1 and 2½ notes had also incidentally been printed, intended for issue in North Borneo, which Indonesia saw as a possible extension to its territory due to the power vacuum in the region at that time.
Read more about this topic: Riau Rupiah