Coins

Here is a photo of some Australian coins.
From left to right:
5 cents; 20 cents; 50 cents; 1 dollar; 2 dollars
They also have a 10 cent coin which is larger than the 5 cent coin, but smaller than the 20 cent
Do you notice any similarities or differences from Canada's set of coins? (I will give some coins to your teacher so you can see them up close)