"The colony of New South Wales had two periods when its own distinct coinage was minted.
"To overcome a shortage of coins, Governor Lachlan Macquarie took the initiative of using £10,000 in Spanish dollars sent by the British government to produce local coins by punching out their centres and stamping the two resulting pieces with new values: five shillings for the outer rim pieces (now known as "holey dollars"), and fifteen pence for the central plug (now known as a "dump"). Apart from doubling the amount of physical coins in circulation, this also had the effect of making them unsuitable for export, so they stayed in the colony. Of the 40,000 Spanish dollars imported, 39,910 holey dollars and 39,910 dumps were made, with the balance assumed to have been spoiled during the conversion process. On 1 July 1813 Governor Macquarie issued a proclamation "that the said Silver Money shall be a legal Tender" and that set their value. The converted coins went into circulation in 1814. From 1822 the government began to recall the coins and replace them with Imperial sterling coinage. By the time the holey dollar was finally demonetised in 1829, most of the 40,000 coins in circulation had been exchanged for legal tender and melted down into bullion. Experts estimate that only 350 Holey dollars and 1,500 dumps remain."
[https://onlinecoin.club/Coins/Country/New_South_Wales/filter/4/]