The Australian two ounces silver piece (abbreviated as 2 oz and designated with Ag for "silver") is a bullion and commemorative 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.
The Mint says about this coin:
Crafted from 2oz of pure silver with a high relief design, this exquisite low mintage piece celebrates Australia’s wild horse - the brumby.
Mobs of brumbies that famously roam the Australian Alps are descended from lost, abandoned or escaped horses that in many cases belonged to early colonial settlers. Free, independent and naturally adapted to its rugged environment, the brumby holds a special place in the heart of many Australians as a symbol of our national character. | 
Search for Australia: Silver Two Ounces 2022 Australian Brumby on eBay 
