Nobody keeps a list, but it would be a fair bet that many thousands of coins are damaged either deliberately of accidentally each year.
As coins are returned to the bank or the Royal Mint, staff weed out damaged or worn coins and recycle them.
All Australian notes and coins represent Australia.
Apart from the fact that Australian banknotes have Australia plastered all over them, they have famous or significant Australians featured on the notes, often with Australian themes or icons.
Most non-commemorative Australian Coins have indigenous Australian animals on the reverse except for the 50 cent coin which has the Australian Coat of Arms, and the Two Dollar coin which features an Aboriginal elder, the "Southern Cross constellation" and the "Grass Tree".
No.
There is no recommended chemical to clean defaced currency. Tampering with or attempting to alter currency is illegal in most countries. If you encounter defaced currency, it is best to contact your local bank or financial institution for guidance on how to handle it.
The lower denomination banknotes get a pretty hard time in circulation and wear out very quickly and are easily torn or otherwise defaced. As with many other countries, Australia replaced the lower denomination notes with coins. The Royal Australian Mint expects to get 40 to 50 years from a coin.
Vandals have defaced the pictograph again.
Vandals defaced paintings on display in the Art Gallery.
apparently Australia has the most coins because our coins keep changing
Flush it?
The first exclusively Australian coins were issued for circulation in 1910. Any coins circulated in Australia prior to 1910 were British coins. Occasionally there were coins from other countries suitably restruck for circulation in Australia.
more resources will be used replace defaced money
While Australia remains a Constitutional Monarchy, the reigning king or queen will be on all of Australia's coins as the nominal "Head of State" (Queen of Australia). Currently, and since 1953, Queen Elizabeth II has featured on the obverse of all Australian coins.
You are in Australia - maybe - and have 4 coins of 50 cents each.
At the Royal Mint in Canberra, Australian Capital Territory (capital city of Australia).