What am i looking at here?

[Heinrich Doppler]

This fossil was found on one of Sweden's more well known Islands Gotland during my holiday travels. This Island Is rich In fossils from the Silurian period.

 

What confuses me Is the pattern that looks just like a Favosite or Honeycomb coral yet the shape resembles that of a shell from a turtle? It Is oddly symmetrical, as the pattern mirrors pretty much from the center of the fossil. I can not see any underlying structures.

 

What Is this?

 

P.S - I have zero expertise with fossils of any kind.

Edited August 7, 2022 by Heinrich Doppler
Correction

[IsaacTheFossilMan]

A big, warm Velkommen to the Forum from the UK!

 

I can see the confusion, but I do not see any bilateral symmetry. Based on the deep grooves between each of the "lumps", I would presume this is a water-worn Halysites coral

.

 

Note the geometric, but not strict, formation of the shape. I presume the gaps have been infilled with matrix, and the original corallite worn away.

[Heinrich Doppler]

Thank you!

 

Very cool, I would have never guessed this one right. Now I can finally stop staring at this piece! :-)

 

 

[IsaacTheFossilMan]

1 minute ago, Heinrich Doppler said:

Now I can finally stop staring at this piece! :-)

 

I wouldn't say that, it's too pretty to stop looking at!

 

Welcome, and congratulations, my friend!

[piranha]

Instead of a halysitid it compares well with a favositid. Perhaps something similar to: Favosites gothlandicus

[Heinrich Doppler]

@piranha

 

The pattern matches indeed, the coincidental shape of It coupled with the pattern Is what messes with my head.

Thanks for your reply!

[IsaacTheFossilMan]

43 minutes ago, piranha said:

Instead of a halysitid it compares well with a favositid. Perhaps something similar to: Favosites gothlandicus

 

Awesome! I didn't know of Favosites from Gotland!

[TqB]

The surface texture and graduated size of the polygons look more like a piece of crinoid calyx than a favositid.

 

The vertical section at the sides looks wrong for coral as well.

Edited August 7, 2022 by TqB

[piranha]

29 minutes ago, IsaacTheFossilMan said:

Awesome! I didn't know of Favosites from Gotland!

 

Stel, J.H. 1978

Environment and Quantitative Morphology of some Silurian Tabulates from Gotland. Scripta Geologica, 47:1-75  PDF LINK

[IsaacTheFossilMan]

22 minutes ago, TqB said:

The surface texture and graduated size of the polygons look more like a piece of crinoid calyx than a favositid.

 

The vertical section at the sides looks wrong for coral as well.

 

I think you might be onto something.

[TqB]

13 minutes ago, IsaacTheFossilMan said:

 

I think you might be onto something.

Thanks, I'm fairly sure it's crinoid now.

Edited August 7, 2022 by TqB

[IsaacTheFossilMan]

I'm 80% certain it's a calyx, I'm with Tarquin. It doesn't show tabulae typical of such type of coral

[Heinrich Doppler]

Thanks everyone for answering!

 

After looking I would bet It's the calyx of a Sea Lily as both shape and pattern Is similar. Super cool! :-)