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turtlefoot

Bryozoa or something different?

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turtlefoot

Hi All,

 

I picked up this rock in my back yard a couple of days ago.  I picked it up because I saw a couple cross sections of rugose coral and some fenestrate bryozoan fossil pieces.  When looking at it later, I noticed this feature.  I haven't found anything like this before.  Is this just a different type of bryozoa?  These little marks also look like some tiny Platycrinite crinoid pieces.  This was found in Howell County, Missouri, USA.  It came from the Ordovician Period.  These lines measure approximately 23mm in length and measure approximately 0.79mm wide.  The individual spots are oval in shape and measure approximately 0.38x0.79mm.  I don't know if it shows well in the first image, but this feature appears to be in a fracture in the host rock.  There is still some rock covering the feature in the fracture.  Any assistance or direction that you can give me is greatly appreciated.

 

Thanks for your time,

Doug 

001.jpg

003.jpg

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grandpa

Looks like the design of a blouse my wife had in the '70's - one of my favorites from her wardrobe at the time.  Not that this helps a bit, just sharing fond memories from a young married couple now going on 52 years of being in love.  To keep on topic -  I've collected a number of fossils over those years, but none from MO.  (Sorry!:blink:)

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turtlefoot
3 minutes ago, grandpa said:

Looks like the design of a blouse my wife had in the '70's - one of my favorites from her wardrobe at the time.  Not that this helps a bit, just sharing fond memories from a young married couple now going on 52 years of being in love.  To keep on topic -  I've collected a number of fossils over those years, but none from MO.  (Sorry!:blink:)

I just celebrated my 22nd anniversary.  I am aware of a very similar pattern on clothing back in the 1970's.  I enjoy hearing about fond memories of others.  I really appreciate the post my friend.

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Rockwood

The frontal walls of bryozoan zooicia is the best I can come up with for the pattern.

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TqB

I'm wondering if it's echinoderm, though I don't know any that fit. The holes may be pore pairs.

The right hand area of your photo seems to show a polygonal pattern, possibly plate structure. Any chance of another shot of this area?

 

5e204a65ea234_Screenshot2020-01-16at11_32_29.jpeg.fb2e80b75d3f350ae5dfc811295993bb.jpeg

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Rockwood

Even stomata in plant material wouldn't be too far out in left field.

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minnbuckeye
1 hour ago, Rockwood said:

Even stomata in plant material wouldn't be too far out in left field.

 

This piece intrigues me in that I regularly hunt the Ordovician. I doubt it is plant based on the age of the formation. But have no guess as to what it is. Echinoderm was my first impression when looking at this. I always look before I read for some reason.

 

Mike

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turtlefoot
1 hour ago, TqB said:

I'm wondering if it's echinoderm, though I don't know any that fit. The holes may be pore pairs.

The right hand area of your photo seems to show a polygonal pattern, possibly plate structure. Any chance of another shot of this area?

I will get some more pics later this morning.  Thanks!

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Peat Burns

I found a very similar fossil in the Mississippian of Silex, Missouri (see below).  We never came up with an ID with which we (the forum) were comfortable.  Would love to know exactly what they are...

 

My specimen is more or less flat, and although "shaped like a brachiopod" shell, I don't think it is.  It might very well be an internal section of something. 

 

Resized_20180626_220454_4789.jpeg

20180627_225537.jpg

 

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turtlefoot
3 hours ago, Peat Burns said:

I found a very similar fossil in the Mississippian of Silex, Missouri (see below).  We never came up with an ID with which we (the forum) were comfortable.  Would love to know exactly what they are...

 

My specimen is more or less flat, and although "shaped like a brachiopod" shell, I don't think it is.  It might very well be an internal section of something. 

 

Resized_20180626_220454_4789.jpeg

20180627_225537.jpg

 

That's an interesting fossil.  It is very similar, if not the same fossil or species.  When I get a chance to get the camera out, I will get more images and do more research.

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turtlefoot

Here are some more images of this fossil.  The first image shows an end break and appears to show that there is possibly some depth or even some sort of layers or division.  I am sorry if I am not wording this well.  The second image just shows where the break is located on the fossil itself.  The feature where the break in the rock is, is about 1mm deep.  When looking at the end, there are indications of the same feature for the other rows.  

 

I believe that the oval features are edges of a larger feature or something similar.  If you look at the last image (sorry about the quality of it) you will see where I put some lines on it.  I know that is might be hard to see without having the rock in hand, but the end feature where the rock is broken, it really looks like the ovals are edges of something.  I am doing a poor job describing what I mean.  Think of a blade of grass and one line of the ovals features are the edges of the blade on each side (two rows of the oval features for each blade of grass).  I know it isn't grass, but that I the only way I can describe it right now.

 

Sorry for rambling.

End Break 001.jpg

End Break 002.jpg

Connections 001.jpg

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turtlefoot

Here is another image.  This image shows the fossil near the break in the rock (top of the image) is not laying flat, but as it goes away from the break, it does lay flat (bottom of the image).  This isn't the best image for it, but you can see a distinct line on the right side.  These lines are faint, but they are there between the rows of oval features.  

Close View 001.jpg

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Peat Burns

@turtlefoot can you elaborate on the source of your fossil?  You said your back yard. Did it come from a rock outcrop, or was it loose in soil / gravel?  Just want to make sure that it is, in fact, Ordovician and not transported from another outcrop / time period.  I got mine within a mile of Ordovician bedrock in a stream bed with Mississippian chert near Silex.  Does your rock evervesce with acid?

 

It does look similar to the Ordovician rock I collected.

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turtlefoot

This image shows how the rows of ovals features fan out.  If you look at this image.  The rows are closer together at the top than they are at the bottom.  Once again everyone, I really appreciate all of your time and advice with this fossil.

Wide View 001.jpg

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Peat Burns

Does there appear to be any evidence of continuation of the "rows" into the adjacent rock face?  In other words, are the features only like an imprint, or is it likely the fossil is a section of a more 3-dimensional object?

20200116_145157.thumb.jpg.3e7260e9d6d1ac77091148dea8165b29.jpg

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turtlefoot
3 minutes ago, Peat Burns said:

@turtlefoot can you elaborate on the source of your fossil?  You said your back yard. Did it come from a rock outcrop, or was it loose in soil / gravel?  Just want to make sure that it is, in fact, Ordovician and not transported from another outcrop / time period.  I got mine within a mile of Ordovician bedrock in a stream bed with Mississippian chert near Silex.  Does your rock evervesce with acid?

I guess that my description of where it was found was pretty poor.  I live in the middle of the National Forest.  The part of my back yard where I found this is actually a seasonal creek and is probably 100 yards from my back door.  We personally cleared the land and I can tell you this rock was not transported from another area.  The closest Mississippian chert is approximately 60 miles away.  The area that I found it in is like pretty much all of the areas that I hunt.  I just walk the dry seasonal creeks, or creek banks and scour the rocks.  That is how I found this one.

 

I do not know if this rock will evervesce with acid.  I will have to test it in an hour or so.  I am getting ready to leave the house for a bit.  Will vinegar be strong enough acid or do I need to get something stronger out of the chemical lock up?

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Peat Burns
4 minutes ago, turtlefoot said:

I guess that my description of where it was found was pretty poor.  I live in the middle of the National Forest.  The part of my back yard where I found this is actually a seasonal creek and is probably 100 yards from my back door.  We personally cleared the land and I can tell you this rock was not transported from another area.  The closest Mississippian  I am getting ready to leave the house for a bit.  Will vinegar be strong enough acid or do I need to get something stronger out of the chemical lock up?

Vinegar might work, but "Sno-bowl", "The Works", or similar toilet cleaner (HCl) would be better.  Or if you have any muriatic acid laying around (HCl). Just a drop will do (not on the fossil part, obviously :))

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TqB
7 minutes ago, Peat Burns said:

Does there appear to be any evidence of continuation of the "rows" into the adjacent rock face?  In other words, are the features only like an imprint, or is it likely the fossil is a section of a more 3-dimensional object?

20200116_145157.thumb.jpg.3e7260e9d6d1ac77091148dea8165b29.jpg

It looks like an internal mould on that photo, with dissolved shell space under the matrix (chert?) on the left.

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turtlefoot
5 minutes ago, Peat Burns said:

Vinegar might work, but "Sno-bowl", "The Works", or similar toilet cleaner (HCl) would be better.  Or if you have any muriatic acid laying around (HCl). Just a drop will do (not on the fossil part, obviously :))

I have muratic acid, and others if needed.  When I get a chance I will test it. 

 

10 minutes ago, Peat Burns said:

Does there appear to be any evidence of continuation of the "rows" into the adjacent rock face?  In other words, are the features only like an imprint, or is it likely the fossil is a section of a more 3-dimensional object?

 

The adjacent rock face has other fossils on it.  There are actually multiple fossils in this one rock.  Looking closely, it really only seems to be about 1mm thick.  It does continue under the piece of rock that hasn't broken off of it.  This can be seen in the images.  There is a fracture in the rock that runs the entire circumference of the rock on the same plane of the fossil though.

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turtlefoot
41 minutes ago, Peat Burns said:

 ...Does your rock evervesce with acid?

There is absolutely no reaction with HCL.

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Peat Burns
14 minutes ago, turtlefoot said:

There is absolutely no reaction with HCL.

Hmmmm.  Might need to do a Moh's hardness test.  It might be chert and possibly stream transported.  I can't recall off hand how reactive dolomite is.

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