Roger Need Your Help - What Is it?

[greywolf22]

I found all these yesterday in a small area about 2 ft x 2 ft in Bentonite soil near Study Butte Texas. There was nothing else like it in the area that looked anything like it. The faces were exposed to the air, with the rest buried under ground. The domes were pointed upward. I do not know what they are. I am thinking along some type of fossilized fungus, maybe an ancient mushroom.

Top

Bottom

Group

Jack
   Attached files 

[turkeytail]

Never seen anything like it? Weird.

[greywolf22]

Got me stumped and thats OK. Need the challenge.

[wmwallace]

Unique to say the least Jack, Kinda simulate the cones we have here in Ohio, but those are usually made out of hardstone. They almost look like bone, although once you mentioned mushrooms you might be on the right track, they kinda look like mushrooms in shape. Neat, let us know if you find anything out, got me intrigued.

[greywolf22]

I may take the by the Museum of Natural History in Houston and see if they can tell me what they are.

[gregszybala]

Jack, you ever find out what these are?

[Butch Wilson]

Kinda looks like.............Jack, ain't there a lot of cows in Texas ?
Butch

[greywolf22]

Maybe Roger can tell us what they are.
Jack

[CliffJ]

I think that they might be plant fossils called cycads. They were like palms, so maybe the top/cone of either palms or cycads- both petrified wood.

[greywolf22]

Cliff
Thanks for the information. Now I can put a name on them.
Jack

[painshill]

Jack
I'm just about to catch a very early morning train to Brussels. Back in two days. I'll have closer look then.
Roger

[tomclark]

mud bubbles boom

[greywolf22]

Might be.
jack

[rmartin]

Where's Roger? I want to what he thinks there things are. I sure don't have a clue.

[painshill]

rmartin wrote:

Where's Roger? I want to what he thinks there things are. I sure don't have a clue.

  I’m just back from Belgium where the only really good thing is the beer (especially Leffe Blonde). I still enjoy hitting the nearest bar and asking for a large blonde.  :whistle: Don’t try this outside Belgium. :laugh:
Soft-bodied things like mushrooms with so much water and so little structure don’t normally fossilize. I have seen a couple of speculative fossilized mushrooms but nothing that’s been confirmed.
These are rocks, but we get a new word for our vocabulary here. “Mimetolith” from the Greek mimetes (an imitator) and lithos (stone): a natural topographic feature, rock outcrop, rock specimen, mineral specimen, or loose stone the shape of which resembles something else e.g., a real or fancied animal, plant, manufactured item, or part(s) thereof.
What you have, Jack, are nice examples of clay concretions, normally cemented together with calcareous minerals such as carbonates. We call them “Imatra Stones” after the Imatra Cascade of the Vuoska River in Finland where they were first described.
They are normally found in clay-rich silt beds (that’s essentially what bentonite is… an impure clay) and are formed underneath running water when the current swirls particles of clay and silt together in a circular motion. Hence, downriver from waterfalls (ancient ones) is a good place to look.
They are characterized by the presence of bedding planes passing through them and are normally flattened parallel to the bedding planes, giving them a stacked disk appearance with a domed top. Frequently, they just sit on top of loose sediment and have a have a flat, smooth base like this specimen from the Pleistocene Clay Bluff of Block Island, Rhode Island.


If they were more firmly attached, they may break off the underlying beds, exposing the interior radial pattern (like yours) that is typical of the way carbonates crystallize.
Typically, they range in size from about 1 to 5 inches, but they also can overlap to give multiples like these (from Finland):

They are also frequently found along the Connecticut River in Massachusetts where the deposits are over 10,000 years old. Here’s an example:

Native Americans who lived close to the Connecticut River in Hampshire County called them “puddle stones”. They were apparently treasured as decorative and ceremonial items and I have seen it suggested that they might have been used as a form of currency.
So, rocks, but not "just a rock".
Roger