Full set of carded coins x 5, with 'S' Mintmark.
Spiny King Crab/ Brittle Star/ Cactus Urchin/ Bigfin Squid/ Dumbo Octopus
 
The Creatures of the Deep Postal Numismatic Cover contains an Australia Post envelope privy mark coin and is limited to just 7,500.
The stamp is printed as part of the design and is postmarked -
First day of issue | 18 April 2023 | Canberra ACT 2601