@Diverdude76 16 April 2021 more from that month

This is a sand dollar I found scuba diving the other day. This is a good size, and not broken which is often the case when found on a beach. Sand dollars are species of flat, burrowing sea urchins belonging to the order Clypeasteroida. Some species within the order, not quite as flat, are known as sea biscuits. Sand dollars can also be called "sand cakes" or "cake urchins".