ID Assistance Request

[Incognito Rockhound]

I’ve been doing a lot of river collecting this year and found some a couple of items have really stumped me. 

 

I’m hoping you all can help me identify them.  The river I collected them from is in Middle Tennessee and is a mix of Ordovician and Devonian (from Chattanooga Shale)

 

As always, thank you for your assistance!

 

Note: Some of these pics were taken through my 10x BelOMO.

 

 

 

 

 

 

[Incognito Rockhound]

2 minutes ago, Incognito Rockhound said:

 

 

 

 

[Incognito Rockhound]

[ynot]

The first piece looks like an iron incrustation, not a fossil.

Not sure about the second piece.

[Incognito Rockhound]

I’ve searched the Internet and the only thing I’ve found that looks even remotely similar is Placoderm

[Incognito Rockhound]

I’ve magnet tested both of them because I find indeterminate scrap metal in the river from time to time.  Neither one of them had any reaction to the magnet.

[ynot]

2 minutes ago, Incognito Rockhound said:

I’ve magnet tested both of them because I find indeterminate scrap metal in the river from time to time.  Neither one of them had any reaction to the magnet.

Most iron minerals are not magnetic.

[Incognito Rockhound]

This is one of the pictures I found on the Internet 

[Incognito Rockhound]

I’ve also found pieces in the same vicinity that have a lot of little bumps all over them

[Incognito Rockhound]

10 minutes ago, ynot said:

Most iron minerals are not magnetic.

That is good to know - thank you!

[Incognito Rockhound]

Another pic from the Internet (note: I didn’t add the red arrows)

[ynot]

Iron minerals often form in cracks in rock, sometimes completely filling the crack.

I don't see it being placaderm, but wait for other opinions.

 

 

[Ludwigia]

I don't think that the pieces come from Placoderm either. If anything, then they could be bits of shell from some indeterminate molluscan fauna. Have you researched your site to find out if at least signs of Placoderms have been found there in the past?

[Incognito Rockhound]

2 hours ago, Ludwigia said:

I don't think that the pieces come from Placoderm either. If anything, then they could be bits of shell from some indeterminate molluscan fauna. Have you researched your site to find out if at least signs of Placoderms have been found there in the past?

 

Unfortunately, the site isn’t mentioned on the Internet for any finds of any type.  

 

Don’t get me wrong - if this isn’t Placoderm, I’m not going to be crushed.  I’m trying to use this as a learning experience - anything Devonian is completely new to me so I know I’m going to make a lot of mistakes.  I also want to make sure this isn’t anything I am going to kick myself over if I return it to the river and it turns out to be something like a Placoderm.  

 

I have an agreement in place with my husband - we live in a small townhome with very limited storage.  I promised to only keep my very best finds and return all others back to the source.  C’mon - what harm can keeping bins of fossils under beds (and the attic, closets, cabinets and other free places) have as long as they are out of sight?   

[Kane]

I agree that it doesn't seem consistent with placoderm. The ones we find up here commonly have raised nodules that are fairly distinct and relatively evenly spaced (think goosebump texture). I think an artifact of mineralization or weathered molluscan fragments are good guesses. But if it did turn out to be placoderm, that would be really neat!

[JimB88]

Placoderms are not found in the Nashville area, the rocks are too old. The only place in TN Ive read about them being found is NE of Knoxville in the Chattanooga Shale (but that is sketchy at best.)  I'd say its bits of broken shell material, most likely from bivalves or brachiopods.

[Incognito Rockhound]

Thank you everyone - as always, your assistance is GREATLY appreciated!