Brachiopod or bivalve

[Brian James Maguire]

This was found in the Carboniferous limestone of the Malahide formation , east coast Dublin Ireland,

[Fossildude19]

Orthid brachiopod, I believe.

 

Cropped and rotated:

 

[Brian James Maguire]

Just now, Fossildude19 said:

Orthid brachiopod, I believe.

Yet another first for me! I have orther orthids but not like this, thanks Tim

[TqB]

I think it may be Schizophoria resupinata (which is indeed an orthid) or very close. (Though always aware that brachiopods show a lot of homeomorphy and are very tricky!)
I find them quite commonly in later Carboniferous limestones, basal Namurian.
This one's silicified so rather sugary looking:

 

[Brian James Maguire]

Fantastic info as always @TqB