Dollar Coins

Well, you see, here "down under" on the opposite side of the planet we are actually upside-down from the USA. It all works out if you look at the coins while standing on your head. Just wait until they bring out a $5 coin. Will need a microscope to see it!

Seriously, I have no idea. Apparently in Australia size doesn't matter.

At 20.62mm, our $2 coin is the second smallest coin, only beaten by the 5¢ at 19.41mm.

In order of size there is 5¢ 19.41mm, $2 20.62mm, 10¢ 23.6mm, $1 25mm, 20¢ 28.52mm, 50¢ 31.51mm which is our largest circulation coin.

G'day, when the $1 was introduced, it was the first Australian coin of that composition. A size was picked, and we were all happy.
When the $2 was introduced, it was decided to use the same composition. Logically, the $2 should have been bigger, but someone persuaded the government that it would be cheaper to go the other way.
New Zealand got it the right way around.
The $2 is also insulting in its design.
The $5 was introduced for circulation in 1988, but in limited quantity, so that they all disappeared into hoards within a week. So, they were a failed experiment: indeed, they were doomed from the start. The government must have realized that the "collector factor" can only be overcome by weight of numbers.

G'day, Inflation ? I'll show you inflation: all of the 1966 coinage featured one animal (or CofA) per coin. The 1984 dollar coin needed five kangaroos to maintain some spending power.

Reminds me of my Mum's observation:
"In 1960, Pig-Iron Bob said he's put value back in the pound; but in 1966 he abolished the pound."

Peter in Oz