Can anyone please tell me what this is? (Found on beach in Pembrokeshire)

[Milliways]

I have been googling but limited signal as camping, and I don’t know how to search an image, but found lots of these on a beach today and have never seen them before, so wondered what lived in them! They are very thin and fragile, but so pretty.

Found my first mermaid purses last month, but managed to Google those with a description, failed with these!

Sea Urchin shell

Echinoid i think.

Fossilised sea urchin?

Yes sea potato sea urchin shell. We used to find them as kids.

www.wildlifetrusts.org/wildlife-explorer/marine/starfish-and-sea-urchins/sea-potato

Thank you! I have been scrolling through shells and molluscs and forgot sea urchins.
DH thinks I should have grown out of shell collecting now, but that’s the fun of a beach walk. Never seen these before and this beach had them everywhere.

Looks like a flattened baseball to me 😂

I think their common name is "sand dollars".

Sea potato. The live ones are covered in fur. We saw loads of them on the beach the day, they're so weird.

Sand dollar

They were in an episode of Andy's Dinosaur Adventures, so naturally I'm now an expert 😂

I thought it was Wilson at first…

It’s an Echinoid.

Sand Dollars are different animals

Amazing OP thank you! I found one last week with some fur attached- I thought it was an animal skull!

I found a fossilised one of those when i was a kid.

I think my DM still has it on her bookshelf.

I’ve often seen these but never knew what they were! As for growing out of shell collecting - what a sad day that would be! A beach near me has lots of cowrie shells and I can amuse myself for hours scouring the beach for them. Rockpooling too - hours of fun!