<p>It is a chemical concretion. the shape and structure are a common form of concretion. there may be a tiny flake of fossil that acted as a seed for chemical deposition but this could be microscopic or long dissolved. the fibers are likely bacterial.</p>
<p><a href="https://i.sstatic.net/zyyuc.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/zyyuc.png" alt="enter image description here" /></a></p>
<p><a href="https://i.sstatic.net/CaC9G.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/CaC9G.jpg" alt="https://64.media.tumblr.com/5a72154ffff42462f7164519b3e63d20/tumblr_p0oghyxcGo1sq04bjo1_250.jpg" /></a></p>
<p><a href="https://onlinelibrary.wiley.com/doi/full/10.1002/dep2.139" rel="nofollow noreferrer">https://onlinelibrary.wiley.com/doi/full/10.1002/dep2.139</a></p>

CC BY-SA 4.0
2022-07-23T14:18:58.207Z
Thanks! I've read a part of the article and a few Wikipedia articles and think I kind of understand it. But what do you mean with "the fibers are bacterial"? Are they fossils of bacteria or a more recent bacterial phenomenon?
ductTapeIsMagic
CC BY-SA 4.0
2022-07-24T07:14:50.573Z
thes fibers are recent bacterial
Weiss
CC BY-SA 4.0
2022-07-24T11:09:34.780Z
Thanks for your help everybody!
ductTapeIsMagic
CC BY-SA 4.0
2022-07-23T13:05:34.267Z
2022-07-23T13:05:34.267Z
John
<p>So, i found a weird structure in a piece of jurassic limestone. It is cylindrical and roughly one cm in diameter, enters the stone on one side and leaves on the other. Under the microscope, you can see particles of limestone/calcite at the inner walls, partially being held in place by some hair-like fibers. Is this a fossil, and if yes, what kind of animal or plant could this have been? Or is it something anorganic?</p>
<p>I'm new here, please tell me if i forgot to mention anything important. Thanks in advance.</p>
<p>Here are some pictures:
<a href="https://i.sstatic.net/4hHzH.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/4hHzH.jpg" alt="enter image description here" /></a></p>
<p><a href="https://i.sstatic.net/5Xp9A.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/5Xp9A.jpg" alt="enter image description here" /></a>
<a href="https://i.sstatic.net/1YC4j.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/1YC4j.jpg" alt="enter image description here" /></a></p>

CC BY-SA 4.0
2022-07-20T12:16:54.800Z
Hi it is hard to tell only from pictures! It is possible to be something fossil however it also can be some mineral structures
Weiss
CC BY-SA 4.0
2022-07-20T12:49:13.287Z
What could I do to identify it or what further information  would be needed for that? I've found these things a few times now and am really wondering what it is.
ductTapeIsMagic
CC BY-SA 4.0
2022-07-20T13:25:10.057Z
perhaps have a look at lokal fossile guides! It is hard to determine without touching it
Weiss
CC BY-SA 4.0
2022-07-20T13:25:22.560Z
To downvoter: why `-1`? Fossil identification questions are perfectly on topic here. User provided info on location, photos... A comment explaining what could be improved would have been nice...
Jean-Marie Prival
CC BY-SA 4.0
2022-07-20T17:43:22.067Z
I'm impressed, this is the first time anyone has provided pictures via a microscope. Having such a picture of the fibrous material would have been good. My question about the fibrous material is, is it hard or soft, does it break easily? My two thoughts are it might be asbestos or it could be a tree root that has made its way deep into the limestone via cracks within the limestone. However, I'm puzzled by the two brown/reddish rings, the first immediately around the perimeter of the hole & the second some distance from the hole. This might be iron staining associated with the fibrous material.
Fred
CC BY-SA 4.0
2022-07-20T18:29:10.617Z
I justed tested it, the fibers are soft. Upon contact with a needle, the whole structure moved but didn't break, almost like a spider Web. That means it's probably not fossil-old, right? Also, regarding the rings: This coloring of the stone is not unusual there, but it normally is even, this ring-form is unusual. There are, however, some pieces where there is a layer of the red substance between limestone and some calcite crystals. Under the microscope, it has a sponge-like structure, the surface dotted with calcite and some black crystals.
ductTapeIsMagic
CC BY-SA 4.0
2022-07-20T18:35:25.150Z
Also, i just made a test and realised, if hydrochloric acid is dropped on the red layer (on a stone without fossil of course), and swiped with paper towel, the acid turns faintly green, which probably indicates that the red stuff is indeed iron oxide, or at least some iron mineral. I unfortunatly can't perform a more sophisticated proof of iron with my equipment.
ductTapeIsMagic
<paleontology><fossils><paleobotany>
Is this a fossil or something anorganic?
ductTapeIsMagic
# Is this a fossil or something anorganic?

(Asked by: username_0 on 2022-07-20)

So, i found a weird structure in a piece of jurassic limestone. It is cylindrical and roughly one cm in diameter, enters the stone on one side and leaves on the other. Under the microscope, you can see particles of limestone/calcite at the inner walls, partially being held in place by some hair-like fibers. Is this a fossil, and if yes, what kind of animal or plant could this have been? Or is it something anorganic?

I'm new here, please tell me if i forgot to mention anything important. Thanks in advance.

Here are some pictures:
[![enter image description here](https://i.sstatic.net/4hHzH.jpg)](https://i.sstatic.net/4hHzH.jpg)

[![enter image description here](https://i.sstatic.net/5Xp9A.jpg)](https://i.sstatic.net/5Xp9A.jpg)
[![enter image description here](https://i.sstatic.net/1YC4j.jpg)](https://i.sstatic.net/1YC4j.jpg)

**Tags:** paleontology, fossils, paleobotany

> **Comments:**
> **username_1**: Hi it is hard to tell only from pictures! It is possible to be something fossil however it also can be some mineral structures  
> **username_0**: What could I do to identify it or what further information  would be needed for that? I've found these things a few times now and am really wondering what it is.  
> **username_1**: perhaps have a look at lokal fossile guides! It is hard to determine without touching it  
> **username_2**: To downvoter: why `-1`? Fossil identification questions are perfectly on topic here. User provided info on location, photos... A comment explaining what could be improved would have been nice...  
> **username_3**: I'm impressed, this is the first time anyone has provided pictures via a microscope. Having such a picture of the fibrous material would have been good. My question about the fibrous material is, is it hard or soft, does it break easily? My two thoughts are it might be asbestos or it could be a tree root that has made its way deep into the limestone via cracks within the limestone. However, I'm puzzled by the two brown/reddish rings, the first immediately around the perimeter of the hole & the second some distance from the hole. This might be iron staining associated with the fibrous material.  
> **username_0**: I justed tested it, the fibers are soft. Upon contact with a needle, the whole structure moved but didn't break, almost like a spider Web. That means it's probably not fossil-old, right? Also, regarding the rings: This coloring of the stone is not unusual there, but it normally is even, this ring-form is unusual. There are, however, some pieces where there is a layer of the red substance between limestone and some calcite crystals. Under the microscope, it has a sponge-like structure, the surface dotted with calcite and some black crystals.  
> **username_0**: Also, i just made a test and realised, if hydrochloric acid is dropped on the red layer (on a stone without fossil of course), and swiped with paper towel, the acid turns faintly green, which probably indicates that the red stuff is indeed iron oxide, or at least some iron mineral. I unfortunatly can't perform a more sophisticated proof of iron with my equipment.  

---

## 1 answers

### Answer by username_4 on 2022-07-23. Score: 3 | Accepted answer

It is a chemical concretion. the shape and structure are a common form of concretion. there may be a tiny flake of fossil that acted as a seed for chemical deposition but this could be microscopic or long dissolved. the fibers are likely bacterial.

[![enter image description here](https://i.sstatic.net/zyyuc.png)](https://i.sstatic.net/zyyuc.png)

[![https://64.media.tumblr.com/5a72154ffff42462f7164519b3e63d20/tumblr_p0oghyxcGo1sq04bjo1_250.jpg](https://i.sstatic.net/CaC9G.jpg)](https://i.sstatic.net/CaC9G.jpg)

<https://onlinelibrary.wiley.com/doi/full/10.1002/dep2.139>

> **Comments:**
> **username_0**: Thanks! I've read a part of the article and a few Wikipedia articles and think I kind of understand it. But what do you mean with "the fibers are bacterial"? Are they fossils of bacteria or a more recent bacterial phenomenon?  
> **username_1**: thes fibers are recent bacterial  
> **username_0**: Thanks for your help everybody!  

---

