Help IDing These Stone Nodules from Missouri

[MObushwhacker]

These stones or found along gullies that have washed away the clay material leaving them exposed. There are no other stones present and some of theses stone can be seen embedded in the clay itself. Most of the nodules have a navel as outlined in the pictures the insides is a solid granular material and minimum brown in color. The closes thing that I have seen representing there appearance is watching the shapes produced by a lava lamp. Any help will greatly appreciated.

[GopherDaGold]

They look like petrified sweet potatoes. Or poo.

[Rasputin]

They look like Moqui Marbles (an iron concretion with a sand core) to me.

[Tuberale]

Might/could be coprophytes: literally fossilized poop.

[claymation]

yeah, they look just like moqui stones or moqui marbles. From Missouri ? I thought they are from Utah, I guess they can be found anywhere the conditions are right.

[Yoop]

They are called concretions. Those are most likely calcareous concretions. Actually "sand" with a calcareous cement.

See links:

http://www.priweb.org/ed/concretions.htm (scroll down)

There is a diverse variety of concretions, in shape, material and inner contents. Some concretions have formed around fossils and, commonly , fossil ferns.

Concretions are common in certain areas of Missouri.

Google "concretions" to see the numerous varieties and shapes. Some can get quite large.

[mamabear]

I'm in Bollinger co. & have a lot of those here too. do you find many fossils in Scott co? 'posed to be some good ones.