The Mint says about the set:
"This beautifully-crafted proof coin set celebrates the extraordinary Australian dinosaurs that roamed the country in the Cretaceous Period, a monumental 145 million to 66 million years ago. Featuring Diamantinasaurus matildae - Australia's best-known sauropod, Kunbarrasaurus ieversi, which is covered in armour, the carnivorous Australovenator wintonensis and a herbivorous elaphrosaurine theropod, the collection is a window into Australia’s ancient past. The four coins have been carefully struck using special dies, further enhancing their exquisite design. The accompanying certificate of authenticity validates the collection’s originality and limited mintage of just 5,000. Whether an avid dinosaur enthusiast or coin collector, this 2022 Australian Dinosaurs $1 proof coin set pays homage to another world in what we know today as Australia."
The four dinosaur coins in the set are proof versions of the circulating commemoratives released into circulation through Australia Post on 5 September 2022.