History of the Holey Dollar, Dump and 1778 Holey Dollar
Fewer than 300 Holey Dollars are known to exist. These coins were originally made using various imported Silver Spanish Dollars. Holes were punched through the dollars, creating two Australian coins. The ring became the Holey Dollar while the punched out portion became the Dump.
The 1778 Holey Dollar on exhibit experienced 35 years of circulation before getting punched and converted to an Australian dollar. However, as you can see, the very outer ring shows very good detail just as the inner, re-stamped ring. That alone makes it extremely rare.
Current Coinage
Each Australian dollar is composed of 100 cents. The smallest coin in current circulation is equal to five cents, the one and two cent coins having been discontinued in 1990-92 and withdrawn from circulation. (Cash transactions are usually rounded to the nearest multiple of five cents, although some merchants round down instead.)
The coins that became effective throughout the 1980s and 1990s and are currently in use are as follows:
One Dollar coin (first issued 1984) - a coin featuring five kangaroos and Elizabeth II - gold coloured
Two Dollar coin - (first issued 1988) - a coin featuring an Aboriginal elder and Elizabeth II - gold coloured
Five cent - smallest "silver" coin featuring an echidna
Ten cent - a lyrebird
Twenty cent - the platypus
Fifty cent - the Australian coat of arms.
10 Shillings (1939)
10 Pounds (1952)
1 Dollar 1983 (Queen Elisabeth II; Aboriginal art)