The Australian one kilo gold piece (abbreviated as 1 kg and designated with Au for "gold") is a bullion coin format. Uniquely, in Australia there are two mints authorised to strike legal tender: the Royal Australian Mint (which also makes the country's circulating coinage) and the Perth Mint which only makes collector and bullion coins, as well as other bullion products.
Both mints endeavour to create coins with attractive designs, and to introduce new designs and themes often, in order to raise the numismatic value of the coins over the value of previous metal used.
This massive one kilogram gold coin is dedicated to the participation of the Australian Olympic Team at the Tokyo Olympic Games. The Olympics actually happened in 2021, but the coin is dated 2020 - the year when the Games were scheduled to happen; it was released in September 2021, after the actual Games ended.
The Mint says about it:
The Olympic story speaks to us of facing challenges, overcoming obstacles, discipline and resilience. It embodies fulfilment through achieving our personal best. The spirit of the Olympics resides in all of us, and this spirit will be felt across the world when elite athletes gather in Tokyo, Japan for the 2020 Olympic Games. With this premium 2020 $3000 1kg Gold Proof Coin we honour the personal stories of triumph, challenge and struggle that have been experienced by the Australian Olympic Team, and we celebrate them as they compete in a spirit of friendship at Tokyo.