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Is It A Fossil?


TomTBD

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Hi

I am new to this forum.

I live in Ca and collect minerals, fossils and as an amateur photographer, I am photographing some of my collections.

 

These photos are of an unopened small geode (3 cm, or 1.25 inches tall). They are all of 1 specimen taken at different angles.

Many decades ago I received a bag of small geodes all formed in the same light green volcanic ash. This was among them. No other geodes in the bag had this texture or pattern on the outside. I put it aside thinking it may be a fossilized impression from a prehistoric reptile or tortoise foot. I have never gotten a definitive answer.

Sadly I can’t recall for certain the location for the source of the geodes, but perhaps it was Chihuahua Mexico.

Is this a fossil, or merely some crystallization causing the surface to appear this way?

Any help would be appreciated

 

Thanks Tom

 

DSC_0868-0877.thumb.jpg.52519e4639237db7c06dbb0b99f1167d.jpgDSC_0878-0895.thumb.jpg.d9683bcf308c3871873ab2e28d7c43a9.jpgDSC_0896-0903.thumb.jpg.31582a3e8e035951dbe6396585a648d6.jpgDSC_0994-1003.thumb.jpg.1639e513750e1e1c543effe53517481d.jpg

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Welcome to TFF!

I have never seen a geode that looks like that.

I think it is a mineral deposit, but not sure what minerals are in it.

Neat piece.

Tony

Darwin said: " Man sprang from monkeys."

Will Rogers said: " Some of them didn't spring far enough."

 

My Fossil collection - My Mineral collection

My favorite thread on TFF.

 

 

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Great specimen! - I think it's a concretion with a counter-septarian structure as in fig. D, this paper. Seilacher concretion morphologies (Sorry, thought that was the actual link but the pdf is on the forum somewhere - just click the "fossil forum" search result if you want it.)

(We've seen similar things on here before. e.g  http://www.thefossilforum.com/index.php?/topic/64412-looking-back-at-one-of-my-older-fossils-distorted-root-or-siderite-nodule/ )

 

59fcaf53e79e8_ScreenShot2017-11-03at17_59_45.thumb.png.dd1c6a5b70319deb80c9a46083cfb6cd.png

Tarquin

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That's it, Tarquin! :)

 

" In a less spectacular version of such counter septarian structures, the tangential cracks did not propagate spirally. Instead they formed a round knob in the center of each first-order polygon, thus mimicking the nuclei in a cellular tissue (Fig. 15 (d)). This suggests that the defoliating cracks started from the polygonal cracks of the previous order and propagated towards the center of the enclosed area. "   - A. Seilacher

 

 

 

" We are not separate and independent entities, but like links in a chain, and we could not by any means be what we are without those who went before us and showed us the way. "

Thomas Mann

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Thanks for the quick replies

Not what I had hoped for, but what I had assumed for all these years. The pattern just looks so "organic". Like this picture of crocidile skin:

image.jpeg.3b24e7619b2675f33de4518c42bbdfa0.jpeg

 

Anyway, thanks again for looking into it

Tom

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The problem I have with this being a counter septarian is two fold.

1. The structure is 3 dimensional.

2. There is a distinct color difference between the central disk/ball (black) and the surrounding polygonal structures.

3. I see what look like botryoidal structures on some of the center structures.

Darwin said: " Man sprang from monkeys."

Will Rogers said: " Some of them didn't spring far enough."

 

My Fossil collection - My Mineral collection

My favorite thread on TFF.

 

 

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On 11/3/2017 at 3:36 PM, ynot said:

The problem I have with this being a counter septarian is two fold.

1. The structure is 3 dimensional.

2. There is a distinct color difference between the central disk/ball (black) and the surrounding polygonal structures.

3. I see what look like botryoidal structures on some of the center structures.

 

Wouldn't that be 3-fold?  :headscratch::P 

 

Actually, the counterseptarian in the older post from Icycatelf is 3 dimensional, as well. 

The color is odd, but that could be an accumulation/glutination of a certain mineral.  :headscratch:

 

    Tim    -  VETERAN SHALE SPLITTER

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12 minutes ago, Fossildude19 said:

Wouldn't that be 3-fold?  

Thought of the 3rd while typing and forgot to correct the lead sentence.:rofl: Oh well.:D

Darwin said: " Man sprang from monkeys."

Will Rogers said: " Some of them didn't spring far enough."

 

My Fossil collection - My Mineral collection

My favorite thread on TFF.

 

 

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19 minutes ago, Fossildude19 said:

Actually, the counterseptarian in the older post from Icycatelf is 3 dimensional, as well. 

The color is odd, but that could be an accumulation/glutination of a certain mineral.  :headscratch:

 

 

UJ9Trjz.jpg.3d4ef512d5805ebdfb1a9464af7b7f08.jpgMpq8PCr.jpg.d5166036632c03246e52387259c00e5b.jpg

 

other examples:

Manganese-Iron-Nodule-BSM106152-03.jpg.5f3d59bb7e6b218ae0189c06b5ffe48c.jpgManganese-Iron-Nodule-BSM106152-05.jpg.fd817007acc97b199e1f1982cd895303.jpgManganese-Iron-Nodule-BSM106152-04.jpg.f3cdb6f585e0a26b701e4f84af3161df.jpg

" We are not separate and independent entities, but like links in a chain, and we could not by any means be what we are without those who went before us and showed us the way. "

Thomas Mann

My Library

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1 hour ago, abyssunder said:

other examples:

They do not look the same to Me.

These examples all show an even grain of (mostly) one color.

The original object does not correspond to that criteria.

 

Darwin said: " Man sprang from monkeys."

Will Rogers said: " Some of them didn't spring far enough."

 

My Fossil collection - My Mineral collection

My favorite thread on TFF.

 

 

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I should mention that this stone has been handled a lot. I have had it for about 30 years. Perhaps that has caused some of the raised areas to darken, but the detail has always been pronounced so I’m not sure. It has been a while.

Tom

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  • 2 months later...

Wow, this post never got figured out? I was searching a term and this came up and I started reading it. I was so curious to find out what it was. Bummer that it’s still a mystery. 

I know I’ve seen this or something like it before.

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I absolutely agree that it is another counter septarium. And I FINALLY found the shot of one I took in the field several years ago.

 

CS.jpg

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