A Geode With A Friend? And A Couple More I Am Not Sure About...

[kennedyskorner]

Hiya everyone and thank you for taking a look.

These were all found in Lawrence County, Missouri in the past 2 years.

I'd love to give the exact location, but this is something we did as a hobby together as a family long before I started researching what we found. We would go hiking, or out looking for arrowheads and sometimes find ourselves just digging in areas that felt needed to be investigated. (Creek bends, old tree roots)

So yes, buckets, shelves and bags full of rocks and stones that are either glittery, agatized stones (my favorite), odd stones such as my foot earlier, or stones and rocks that seem to have something in them.

My son, whom is 7, is researching these with me and we are learning as we go.

So far, I have learned how to use a camera somewhat better

The Geode half is approximately 2"

The back of the Geode is a strange almost transparent skin-like material (You can see things like i am assuming are roots, etc. through the surface.)

Front and back

I tried to get some details of the back

This next object is 2 1/2 " long, 1 1/2" at its widest, and 1/2" thick. I am thinking its an impression, or a 'trace' fossil of some kind?

Front and back pics

I tried to get some angles for the depth of the impression:

This one was harder to capture. Its 1 1/2" long and 1" wide. It just seems like something stuck at the end of this rock...The object at the end of the rock is about 1/2-1 cm in size.

If you would like any more information let me know.. I appreciate all your help and experience.

Danie. K.

[tmaier]

The first one looks like a piece of geode, with a smooth outer surface and crystal growth on the inside.

The second one has something that looks like a fossil on the back side. That front side you are most curious about doesn't seem to have any defining features of a fossil that I know of. I've circled the part of the back that looks fossil-y. I don't know what it is.

That third one is a cast of the inside of some creature. It's called an "internal cast". It looks to be the cast of a cephalopod.

cephalopod...

http://www.ucmp.berkeley.edu/taxa/inverts/mollusca/cephalopoda.php

It looks like a mushroom. The stem of the mushroom is the siphuncle, a tube that connects the chambers. The cap of the mushroom is the cast of the inside of one of the chambers. This cephalopod filled with mud, then the mud hardened and the shell dissolved away.

Anyway... that is what it looks like to me.

Edited October 24, 2014 by tmaier

[Herb]

ditto

[tmaier]

You and your son might be interested in looking through this site. It is designed for introducing new people to paleontology.

http://www.paleoportal.org/

Here's a map of the age of the rocks at the surface in south west MO.

http://www.paleoportal.org/index.php?globalnav=time_space&sectionnav=state&name=Missouri

Your area is Carboniferous and about 300 million years old.

Edited October 24, 2014 by tmaier

[kennedyskorner]

You and your son might be interested in looking through this site. It is designed for introducing new people to paleontology.

http://www.paleoportal.org/

Here's a map of the age of the rocks at the surface in south west MO.

http://www.paleoportal.org/index.php?globalnav=time_space&sectionnav=state&name=Missouri

Your area is Carboniferous and about 300 million years old.

Thank you once again for your help. This was some great news and we bookmarked those links I hope the pictures were much better this time. This site is truly a great find for us.

[howard_l]

Just a little tidbit about geodes and fossils. Geodes form long after the ocean sediment has been laid down or diagenetically. They typically have replaced material like gypsum that was also diagenetic. All geodes have to have porosity or a space to form in. In an igneous setting it is gas bubbles in lava. In sedimentary rock that porosity comes from mostly animal activity or the fossil it self. The process that forms geodes typically destroys all recognizable fossil fabric except for a general shape. Occasionally, some of the original fossil is preserved on the outside of the geode. Finding any remnants of a fossil inside the geode would be very rare. Most of the time when you find geodes in a creek or away from the area they were formed, they are the only thing left of the unit where they formed. The quartz is much more resistant than anything else in the Formation that the outer material has been eroded away leaving only geodes.

[kennedyskorner]

Just a little tidbit about geodes and fossils. Geodes form long after the ocean sediment has been laid down or diagenetically. They typically have replaced material like gypsum that was also diagenetic. All geodes have to have porosity or a space to form in. In an igneous setting it is gas bubbles in lava. In sedimentary rock that porosity comes from mostly animal activity or the fossil it self. The process that forms geodes typically destroys all recognizable fossil fabric except for a general shape. Occasionally, some of the original fossil is preserved on the outside of the geode. Finding any remnants of a fossil inside the geode would be very rare. Most of the time when you find geodes in a creek or away from the area they were formed, they are the only thing left of the unit where they formed. The quartz is much more resistant than anything else in the Formation that the outer material has been eroded away leaving only geodes.

Thank you very much for your tidbit of fascinating information. I am learning and appreciate any help. The only thing that seemed odd about the geode to me was the translucent outer material. Someone pointed out to me at a picnic that they thought they saw a Crinoid just under the surface so I felt i had to post and ask.

This was my first geode so I didn't know much about it except it was really pretty and sparkly (I love sparkly After finding that half, someone told me that it was a round or ovalish smooth rock that was just broke in half, I think i smashed about 20 rocks in my yard that even looked like they were kind of round. Haha.

Thanks again, cheers

Danie

[howard_l]

There are some creeks in central KY where you can't kick a rock without it being a geode. The problem is you might have to break open a 20 or more just to find a nice one.

[kennedyskorner]

Ah, I got lucky. This one when i found it was already broke in half and the cluster is a pretty amber color. Thank you Howard, for the link and the response.