The first coins of the Indonesian rupiah were issued in 1951 and 1952, a year or so later than the first Indonesian rupiah banknotes printed, following the peace treaty with the Netherlands in November 1949. Although revolutionary currency had been issued by the provisional Indonesian government between 1945 and 1949, it had all been formed of paper, for metal were too scarce for the internationally isolated government to use as currency.
Due to high inflation in the late 1950s and early 1960s, no coins were minted after 1961, and that which remained in circulation were effectively worthless.
A devalued 'new rupiah' was issued in an attempt to tame inflation in 1965, with banknotes in denominations all the way from Rp0.01 (1 cent) up to Rp100 - no coins were struck at this time. By 1971, however, the economy, and inflation, under Suharto's New Order was stable, and coinage was once again issued, in denominations of Rp1, Rp5, Rp10, Rp25 and Rp50, with Rp100 coins added two years later. Due to inflation, the current coinage now consists of Rp25, Rp50, Rp100, Rp200, Rp500 and Rp1,000, although older Rp1 coins remain officially legal tender for completeness.
Unlike coinage of the Netherlands Indian gulden (which in higher denominations were made of silver or gold), circulating rupiah coinage has always been formed of base metal.
Cent (sen) coinage of the rupiah (1951–1961)
For the first couple of years until sufficient coins had been issued, government cent notes were circulated, of Rp0.10, Rp0.25 and Rp0.50 denominations. No lower denominations were printed, but the old bronze Netherlands Indies gulden coins of ½, 1 and 2½ cents remained as legal tender (higher denominations, starting from 1/20 gulden (5 cents), had been silver, with greater intrinsic metal value).
Coinage, issued in 1951 and 1952, and from then until 1961, replaced the notes as sufficient coinage entered circulation. Under Indonesian law originally enacted by the Dutch, the government was responsible for the issue of money with values below Rp5 (in Dutch times gulden), and hence all coins bore the name of Indonesia, rather than the central bank.
The denominations were Rp0.01, Rp0.05, Rp0.10, Rp0.25 and Rp0.50. The Rp0.01 and Rp0.05 coins had centre holes, similar to the old copper coins of the Dutch, while the other coins were solid. All were aluminium except the Rp0.50, which was cupronickel. Rp0.01 coins were effectively worthless, and only a token number of 100,000 were minted, all dated 1952. Rp0.05 coins were more useful and were also minted dated 1954, as were the Rp0.10 coins.
From 1954, Indonesia began to stop using the Jawi script, which had been a feature of the coins of the Netherlands Indies as well as of past Islamic sultanates in the archipelago. The Rp0.50 coin was the first to be changed, with the Arabic text simply removed from the coin for its 1954-dated minting.
The Rp0.25 coin was the next to have the Arabic removed, with "INDONESIA" replacing its Jawi equivalent for the second minting of the coin, dated 1955 (the Rp0.50 coin was also minted that year).
Inflation meant that the smallest denomination to be minted after 1954 was the Rp0.10, which likewise had Arabic removed from its reverse for its third minting, 1957; Rp0.25 and Rp0.50 coins were also minted in 1957.
After 1957, the cupronickel Rp0.50 coin was debased to aluminium, the same metal as the lower denomination coins (which were never minted again). As a result of this, the Rp0.50 coin, previously the heaviest, but second-smallest coin - slightly larger than the Rp0.01 coin, was now the largest coin in circulation (albeit lighter than its predecessor).
25 rupiah gold coin
A variation of the 1952 Rp0.50 coin was issued in gold with an official value of Rp25 (although with no value on the coin). The coin varied from the Rp0.50 coin by featuring the logo "BEKERDJA-MENABUNG-MEMBANGUN" (WORKING-SAVING-BUILDING) and the Garuda emblem instead of the year and denomination. Like the other 1951–1952 coins, this one has the mintmark of Utrecht.