other
| Country | Australia | Denomination | 20 cents |
|---|---|---|---|
| Year | Mintmark | Royal Australian Mint | |
| Metal | copper-nickel | Purity | 0.0 |
| Weight g | 11.31 | Silver oz | |
| Gold oz | Premium | ||
| Notes | Platypus reverse design introduced with Australian decimal currency in 1966. | ||