The Perth Mint is Australia's official bullion mint and wholly owned by the Government of Western Australia.

 

Established on 20 June 1899, two years before Australia's Federation in 1901, The Perth Mint was the last of three Australian colonial branches of the United Kingdom's Royal Mint (after the now-defunct Sydney Mint and Melbourne Mint) intended to refine gold from the gold rushes and to mint gold sovereigns and half-sovereigns for the British Empire. 

Along with the Royal Australian Mint, which produces coins of the Australian dollar for circulation, The Perth Mint is the older of the two mints issuing coins that are legal tender in Australia.

In October 2011, The Perth Mint created the world's largest, heaviest and most valuable gold coin, breaking the record previously held by the Royal Canadian Mint. 

The coin is approximately 80 centimetres (31 in) in diameter and 12 centimetres (4.7 in) thick, and made of 1,012 kilograms (2,231 lb) of 99.99% pure gold. It features, on the obverse side, the effigy of Elizabeth II, and a red kangaroo on the reverse side. 

It is legal tender in Australia with face value A2 million, but at the time of minting it was valued at A$53.5 million.

According to en.wikipedia