As with Silver Kangaroo coin range the Silver Koala coins show a different design of the featured animal each year, making them highly collectable for investors. Limited mintages ensures that the coins, especially with attractive designs, command a premium in the secondary market. Although mostly seen in 1oz and 1kg sizes, 5oz and 10oz coins are also available albeit rarer to locate. The Perth Mint releases a mix of proof, frosted and bullion finish Koala coins