Large fossils found in Missouri

[JunkOCS]

I found these two fossils here in SW Missouri buy the house. They were both in the same area.  Any help to ID would be greatly appreciated. 

[ynot]

Your pictures are to small to see any detail.

Can You take some closeups of the items in question.

It is better to add 1 or 2 pictures per post, rather than making them small enough to add more.

You can add additional pictures in replies.

 

First impression is chert nodules, but that opinion can change with better pictures.

[JunkOCS]

Thank you for the reply and photo input, here are some more. 

Here are a few more. 

 

One more. Please let me know if they are better or not for viewing?

 

 

[Tidgy's Dad]

Yes, much better for viewing thanks! 

But chert nodules, i'm afraid. 

[Fossildude19]

I agree, not bones. 
Chert nodules in limestone/dolostone.

[abyssunder]

maybe tripolitic chert

 

image from here

 

This thesis might help: Minor, Paul Marchand. 2013. Analysis of Tripolitic Chert in the Boone Formation (Lower Mississippian, Osagean), Northwest Arkansas and Southwestern Missouri. Theses and Dissertations. 890.

[JunkOCS]

Abyssunder...I think you are correct. 

I live a few miles east of the area that’s mentioned in your attached article. Very cool. 

 

[KimTexan]

I have a question for those commenting on it being chert. I believe it is chert too. My question though is can’t you have a chert bone fossil, like a pseudomorph? I have numerous pieces of petrified wood that are chert, so why not bone? 

[jpc]

3 minutes ago, KimTexan said:

I have a question for those commenting on it being chert. I believe it is chert too. My question though is can’t you have a chert bone fossil, like a pseudomorph? I have numerous pieces of petrified wood that are chert, so why not bone? 

That is a very good question.  Wood often gets sicified (=cherty), but bone rarely gets preserved this way.  

 

There... I will leave it as a good question.  I offer no answers.  

[JunkOCS]

Here is an interesting read on pseudofossils:

http://www.bcmnh.org/fauxfossils.html

Edited November 28, 2017 by JunkOCS

[ynot]

2 hours ago, JunkOCS said:

Please let me know if they are better or not for viewing?

Much better, thank You.

As the others have said it is chert nodules.

 

42 minutes ago, KimTexan said:

I have a question for those commenting on it being chert. I believe it is chert too. My question though is can’t you have a chert bone fossil, like a pseudomorph?

The wood You have is most likely agatized, which is also a crypto-crystalline quartzite.

I have seen some bone that is agatized (gem dino bone). 

Have not heard of chert being a replacement agent of either wood or bone.

[KimTexan]

3 hours ago, ynot said:

Much better, thank You.

As the others have said it is chert nodules.

 

The wood You have is most likely agatized, which is also a crypto-crystalline quartzite.

I have seen some bone that is agatized (gem dino bone). 

Have not heard of chert being a replacement agent of either wood or bone.

Doh! Sorry, I’m thinking chalcedony. My brain was on break like I was when I wrote that. (Sheepish grin) Chalcedony, chert what’s the difference? They both start with C. LOL I’m blonde. I have liberty to make those kinds of dingy statements.

[ynot]

1 minute ago, KimTexan said:

 Chalcedony, chert what’s the difference?

The way they form.

 

But You already know that.

[jpc]

Its all cryoto-crystalline quartz.  It is still an interesting question... why is it so common for wood to be replaced with it, and less so with bone?   

[ynot]

Just now, jpc said:

Its all cryoto-crystalline quartz.  It is still an interesting question... why is it so common for wood to be replaced with it, and less so with bone?   

Wood is a softer more permeable material than bone is. It is easier for the silica to penetrate and replace the wood.

(Not positive, but I think wood has some silica in its structure to start with.)

Could also depend on the conditions of burial.

[KimTexan]

1 hour ago, ynot said:

(Not positive, but I think wood has some silica in its structure to start with.)

Could also depend on the conditions of burial.

Bone has silica too. Although I have no idea how much relative to bone. Silica is essential in bone mineralization and healthy bone development. Deficiencies in it contribute to osteoporosis and bone deformities.

 

Regarding bone and various silica forms replacement. I have seen the agate or chalcedony replacement of bone. Chert is still a cryptocrystaline as is chalcedony. Opal is another silica based mineral that is not cryptocrystaline in nature, but it mineralizes bones. So why not chert?

 

Just looking at these items, externally they resemble bone in shape and even in texture in some respects. See the external top left and lower margins. Bone can look similar to that. So can a concretions.

I have excavated bones in the Lance Formation in Wyoming where the bones were ineffect a large concretions casing, which it had to be extracted from. One of the bones were over 50 inches long.

 

 

This picture looks like a knee joint where the two bones were mineralized into one unit.

 

I’m not saying that’s what it is. But it leaves me with reasonable doubt. That said I am not a paleontologist and know very little about th specifics of fossilization processes in various local and conditions of formation.

I am a scientist and was a clinical researcher for over 12 years. One thing I have learned over the nearly 30 years of my science career is that I need to be more open minded to things being different from what I expect or am familiar with. That opens up the possibility for totally new discoveries, thinking outside the box and solving old problems or mysteries.

 

I say that with the question in mind of if chalcedony and opal can mineralized bone then why not chert?

 

I’m just thinking out loud.

[ashcraft]

Petrified wood is not formed by replacement.  It is formed by minerals filling the voids between the cells, usually a silica compound.  Silica compounds are mostly very slightly soluble in water, and most ground water is saturated with it, so as water moves through the wood, it exchanges the silica compounds for other more soluble substances, eventually filling the voids , but the wood remains.

 

It could be that water carrying silica is acidic, which would destroy the bone instead of preserving it.  I have very little experience with fossilized bone, but aren't preserved bones usually phosphatic?  How about really old bones (permian), how are they preserved?

 

Brent Ashcraft

[ynot]

4 minutes ago, ashcraft said:

it exchanges the silica compounds for other more soluble substances,

I thought that was the definition of replacement.

 

55 minutes ago, KimTexan said:

if chalcedony and opal can mineralized bone then why not chert?

Chert forms in the manner of a concretion filling the space between the grains of the rock it forms in. I see no reason why bone can not be fossilized in this manner. But the bone would be encased in the chert nodule rather than replaced by chert. (unless it is a cast.)

I think the conditions that allow chert to form are detrimental to the preservation of bone. This would explain why bone is not (or is seldom) found as a chert fossil.

This is just My thoughts and I may be wrong. Would need someone that specializes in cryptocrystalline quartz formation to explain.

[doushantuo]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[ashcraft]

8 minutes ago, ynot said:

I thought that was the definition of replacement.

 

No, as I said, the wood is still there, it is not being replaced.  Water will only hold so many substances, when it is saturated and comes in contact with something more soluble, it leaves something behind that is less soluble.  Typical hard water is carrying many ions more soluble then silica, as they jostle these ions around, the Silica compounds get left behind.  This is the same way chert infills holes in limestone, not replacing anything.

 

Brent Ashcraft

[ynot]

Thank You @doushantuo

 

 

[doushantuo]

HIGHLY recommended:

[doushantuo]

[doushantuo]

 

from:

 

[ynot]

40 minutes ago, ashcraft said:

No, as I said, the wood is still there, it is not being replaced. 

Brent Ashcraft

Sorry Brent, but I do not agree with this statement.

From online dictionary...

Petrified wood is a fossil. It forms when plant material is buried by sediment and protected from decay due to oxygen and organisms. Then, groundwater rich in dissolved solids flows through the sediment, replacing the original plant material with silica, calcite, pyrite, or another inorganic material such as opal.

 

Petrified wood (from the Greek root petro meaning "rock" or "stone"; literally "wood turned into stone") is the name given to a special type of fossilized remains of terrestrial vegetation. It is the result of a tree or tree-like plants having completely transitioned to stone by the process of permineralization.

 

And finally from wikipedia...

Petrified wood (from the Greek root petro meaning "rock" or "stone"; literally "wood turned into stone") is the name given to a special type of fossilized remains of terrestrial vegetation. It is the result of a tree or tree-like plants having completely transitioned to stone by the process of permineralization. All the organic materials have been replaced with minerals (mostly a silicate, such as quartz), while retaining the original structure of the stem tissue. Unlike other types of fossils which are typically impressions or compressions, petrified wood is a three-dimensional representation of the original organic material. The petrifaction process occurs underground, when wood becomes buried under sediment or volcanic ash and is initially preserved due to a lack of oxygen which inhibits aerobic decomposition. Mineral-laden water flowing through the covering material deposits minerals in the plant's cells; as the plant's lignin and cellulose decay, a stone mold forms in its place. The organic matter needs to become petrified before it decomposes completely.[1] A forest where such material has petrified becomes known as a petrified forest.

 

Respectfully,

Tony