Sea floor (?) fossil

[Richard Beale]

I bought a mixed lot of minerals that included this piece of fine-grained sedimentary rock containing many small fossils. 

Coin in picture is for reference (19mm diameter). 

 

Not much to go on (the seller didn't know where the fossil comes from) but it has a very distinctive structure so I hope it helps the identification. 

The top of the stone shows blob marks but also cone shaped cavities with even striations. These can be seen on the side areas too.

Thank you for any help you can provide!

 

 

[hemipristis]

Conularids?

[Fossildude19]

Cone in Cone structures.

[doushantuo]

Spot on,Tim

CONE-IN-CONE AND BEEF-IN-SHALE TEXTURES FROM DSDP SITE 330,FALKLAND PLATEAU, SOUTH ATLANTIC
John Tarney

DSDP report ,forgotten which one,probably leg 40 or 75

tffconeincone,BEEFdsdp36_2tarney0.pdf

cone-in-cone structures have been known from paleosols as well, so no surefire indicator of submarine deposition 

Edited November 28, 2024 by doushantuo

[Richard Beale]

Hemipristis and Fossildude, Thanks for your ideas. I had considered conularids; I have only ever seen examples from Bolivia.

They seem to have straighter lines than my fossil and a more geometric shape but there is a resemblance.

 

I had never heard "Cone in Cone" structures and the pictures  in the Wikipedia link didn't look a lot like my specimen, but when I Googled the term I found this page: https://serc.carleton.edu/NAGTWorkshops/sedimentary/images/cone.html

and they look very similar.  It is hard to believe that they are not organic in origin.  If it were not for such confident statements of experts I could never have imagined it.

 

Fossildude - I applaud your knowledge of (what is to me) such a rare phenomenon.  It is these never-ending surprises and the kindness of my fellow enthusiasts (in this case Hemipristis and Fossildude) that make this such a wonderful hobby.  If you ever go to Yosemite National Park, you will likely have to pass through the ghost town of Chinese Camp, and there is nothing there except for my general store (and a bunch of abandoned 19th century buildings).  If you stop by I will take you to my local, ammonite location.

 

I am disappointed that my stone is not a fossil, but equally happy that I have an example of cone-in-cone which seems so odd.  I wish I knew where it originated.

 

Regards, Richard

[Richard Beale]

Thank you doushantuo for adding to this conversation (I replied above before seeing your message).  I think this mystery has been solved as you suggest: cone-in-cone.  Something that, until 30 minutes ago I could not have imagined!

Thank you for your kind help!

[Fossildude19]

8 hours ago, Richard Beale said:

am disappointed that my stone is not a fossil, but equally happy that I have an example of cone-in-cone which seems so odd. 

 

 

This is the right attitude.
I have never found one in my nearly 30 years of fossil collecting.

 

I would be pleased with a neat example of a relatively rare geologic sedimentary formation such as this. 

 

Cheers!

[Carl]

On 11/28/2024 at 12:26 AM, Richard Beale said:

Hemipristis and Fossildude, Thanks for your ideas. I had considered conlarids; I have only ever seen examples from Bolivia. They seem to have straighter lines than my fossil and a more geometric shape but there is a resemblance.

I had never heard "Cone in Cone" structures and the pictures  in the Wikipedia link didn't look a lot like my specimen, but when I Googled the term I found this page: https://serc.carleton.edu/NAGTWorkshops/sedimentary/images/cone.html

and they look very similar.  It is hard to believe that they are not organic in origin.  If it were not for such confident statements of experts I could never have imagined it.

 

Fossildude - I applaud your knowledge of (what is to me) such a rare phenomenon.  It is these never-ending surprises and the kindness of my fellow enthusiasts (in this case Hemipristis and Fossildude) that make this such a wonderful hobby.  If you ever go to Yosemite National Park, you will likely have to pass through the ghost town of Chinese Camp, and there is nothing there except for my general store (and a bunch of abandoned 19th century buildings).  If you stop by I will take you to my local, ammonite location.

 

I am disappointed that my stone is not a fossil, but equally happy that I have an example of cone-in-cone which seems so odd.  I wish I knew where it originated.

 

Regards, Richard

Thank you for this perfect reaction! 

[jpc]

This is a nice example of cone-in-cone.  These things are fairly easy to finds in certain Cretaceous marine formations in my area.  I especially like the hollow cone near the egde.  Also, high five for using an old coin (USA Indian Head Penny) AND telling us it is 19 mm in diameter.  We have a very international group here and many, maybe even many between the Canadian and Mexican borders might not know what that coin is.