Found it in a box of my dad's after he passed.
1981 Australia's 50 cent piece.
Try posting that on the World Coin forum... might be more interest there. Or if selling, the BST forum. Cheers, RickO
The homegrown portraits of Chuck and Di aren't great but it's a circulating commemorative. Not so common in these days of NCLT.
Australia has a strong history of issuing circulating commemoratives. They issue plenty of NCLT commemoratives too, especially in the last few decades, and it can be hard to know which is which if all you have is a catalogue list of coins, since they tend to have the same specifications.