Unknown from the Wilson Clay Pit

[dre464]

I found this at the Wilson Clay Pit in July of 2015.  I'm not sure what it is.  Its quite small, approximately 8 millimeters.  It doesn't have the look of a crinoid stem or brachials.  Is it from a crinoid?  Is it possibly a echinoid spine of some type?  It is from the Harpersville Formation, Late Pennsylvanian, Virgilian Stage (288 to 286 MYA).

 

The specimen is below.  The scale is in centimeters.

 

 

Any help is appreciated, as always...

[ynot]

I would say it is a crinoid section.

A picture of the end would help to make sure.

Tony

[Oxytropidoceras]

Yes, I agree. I would identify it as a steinkern, cemented sedimentary fill of the internal space (central axial canal) within a crinoid stem, from which the actual crinoid stem has been largely removed by weathering. Goe see, "Crinoid Columns, Figure 5A. Steinkern (internal mold)" in "Devonian Crinoids and Blastoids at the Falls of the Ohio and Surrounding Areas" at https://web.archive.org/web/20161106003833/http://www.fallsoftheohio.org/DevonianCrinoids-Blastoids.html .

 

Yours,

 

paul h.

Edited November 6, 2016 by Oxytropidoceras
added text

[dre464]

Thanks Tony and Paul!  I hadn't thought about it being the internal space of a crinoid stem!  It makes sense based on the rough texture of the surface.  Normally, the preservation in this area is pretty good, so the rough texture is unusual. 

 

Thanks for the info!

 

Daniel

[abyssunder]

13 hours ago, ynot said:

A picture of the end would help to make sure.

Some columns with similar preservation :

 

[dre464]

Thanks abyssunder.  There are a lot of similarities in this specimen to the ones that Alexandra found; particularly, the ring around each segment.

 

Below are pictures of the ends of the piece.  They don't really reveal a lot to me, but to more trained eyes (i.e., everyone on TFF) they may say more...