This is a very strange rock.

[Pleuromya]

Hello, I found this very strange rock. It has what looks like a fossil impression? And this strange hole that has scale-like structures in it. Is anybody able to tell me anything about this?

Sorry there's no scale, I couldn't find a ruler. It's about 10cm long. I found it in Northamptonshire, UK.

 

Thanks.

 

 

[Pleuromya]

Just a couple of more images.

[Pleuromya]

[digit]

Strange rock, indeed! Not seeing anything recognizably fossil in this one and it looks like some sort of concretion that has been internally eroded (or possibly was always hollow). Possibly, someone here will recognize it but it looks sort of like an ironstone concretion to me.

 

 

Cheers.

 

-Ken

[Pleuromya]

12 minutes ago, digit said:

Strange rock, indeed! Not seeing anything recognizably fossil in this one and it looks like some sort of concretion that has been internally eroded (or possibly was always hollow). Possibly, someone here will recognize it but it looks sort of like an ironstone concretion to me.

 

 

Cheers.

 

-Ken

Ah, thanks.

[caldigger]

Perhaps a concretion that had a cone nucleus that has since eroded out. 

[Pleuromya]

29 minutes ago, caldigger said:

Perhaps a concretion that had a cone nucleus that has since eroded out. 

That's interesting. It was full of clay, and I almost missed it. Do you know what the flat bit could be?

[Rockwood]

You might try bog iron on for size.