The Australian ten kilograms silver piece (abbreviated as 10 kg and designated with Ag for "silver") is an extremely large and rarely used 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 ten kilograms silver coin with a face value of $300 was issued as part of the Perth Mint's Lunar Series III to mark the Chinese Year of the Rabbit (22 January 2023 - 9 February 2024).
The Mint says about it:
First issued in 1996 and now in its third round, the long-running Australian Lunar Coin Series portrays the 12 animals of the ancient lunar zodiac. Annual designs featuring the mouse, ox, tiger, rabbit, dragon, snake, horse, goat, monkey, rooster, dog and pig are depicted in sequence according to the position they finished in the emperor’s Great Race.
In fourth position was the rabbit, which is said to bestow intelligence, creativity, vigilance, and compassion on those born under its influence in 2023 and every 12th preceding year. | 
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