Please help identify

[abyssunder]

John beat me to it.

If I put your specimen in a 90 degrees-rotated position I can see how it resembles the columnar stromatolite of the comparative picture, but there are not enough details to distinguish if there are pillars present or not.

 

 

[Hank]

I've included more photos showing lateral lines in the piece.  I am not knowledgeable enough to determine what a pillar should look like.  If I am understanding what has been discussed, if there are no pillars it is a probable stromatolite.  Would what is in the photos be considered pillars?  Some of the lines look like cracks that were later cemented with another material.

[Malone]

Is it possible that it's a combination of both?

[DPS Ammonite]

8 minutes ago, Malone said:

Is it possible that it's a combination of both?

@Malone, what is "it" and what are "both"?

 

Hank, pillars are organic vertical structures made by stromatoporoids in each of their horizontal lamina. 

[Malone]

12 minutes ago, DPS Ammonite said:

@Malone, what is "it" and what are "both"?

 

Hank, pillars are organic vertical structures made by stromatoporoids in each of their horizontal lamina. 

The article I posted says the picture posted is a combination of stromatolites and stromatopoids(both) It would be what is.

[Malone]

Or could the object in question be a combination of more than one type of organism?

Edited April 21, 2018 by Malone
Clarification

[DPS Ammonite]

13 minutes ago, Malone said:

Or could the object in question be a combination of more than one type of organism?

Theoretically yes this could be an intergrown mixture of both types of organisms. So far we are not sure what this is let alone if one organism is growing on another. Probably microscopic pictures might tell. Hopefully Hank will send a photo of it to Kershaw for an ID.

[Hank]

Photos and a request for identification sent to Mr. Kershaw.  Will let you know when I hear back.

[abyssunder]

In my opinion the structure is too porous for a stromatolite, also I can see laminae and pillars, but to be sure of this, high-res images are needed.

 

comparative picture from here

[Malone]

Leiolite is another form of microbe that I found on the net. Just a thought. To be honest I am not sure that all have been found yet either. I believe it's a microbial colony of some sort. Interesting!

[Malone]

40 minutes ago, abyssunder said:

 

 

comparative picture from here

What is this picture of? Also I read it's rare for stromatolites to contain fossilized microbes.

[Malone]

This is an interesting article.

[abyssunder]

47 minutes ago, Malone said:

What is this picture of?

It's a Middle Devonian stromatoporoid from Ohio. link

I don't know its name (genus / species), but our member Shamalama may know this.

[Hank]

These may be more helpful, taken through a 10x loop.

[abyssunder]

Could you take some 10x magnification photos of the region I chose previously (Sorry to make you work again.) ?

[Hank]

Here is the area you asked for.

[abyssunder]

Thanks for the pictures.
I'll go with stromatoporoid until it will be stated otherwise.

[Tidgy's Dad]

Stromatolite for me at this stage 

Nice, interesting piece, it's a good find whatever it may turn out to be 

[Hank]

Here is an update, Mr. Kershaw reviewed the photos and replied as follows:

Dear Hank,

 

Excuse my small delay, I was travelling back from China yesterday.

 

Your closer pictures do look more like stromatoporoid than stromatolite, but I remain with basically the same problem that the structure can only really be fully seen in a cut block. Therefore I still can't confirm their identification, but if you can get the rock cut and polished then photographed or scanned, it should be possible to work it out. Maybe there is a geology department in your local university that might be able to cut it for you if you ask them?

 

Do let me know; I would like to give you the confirmation you seek, but as with many rocks they need to be prepared in order to reveal their details.

 

Best wishes

Steve Kershaw

 

So my question is should I cut the fossil and if so, where should I cut it?  Should it be split down the length or cut across with the lamina?  I have a full shop with slab and trim saws, as well as the ability to polish.  Would you cut the specimen or just leave it as is?

[DPS Ammonite]

First figure what is the fossil's best side; I like the one in the third photo. Then cut down lengthwise leaving the best half uncut. Polish backside of the display half. You will have a really cool display piece even if we can not figure what it is. Using the other half, cut lengthwise again at a right angle. Cut again parallel to the laminations. Polish cut sides and photograph. Send to Kershaw.

 

You will have photographed three views: parallel to laminations, and two normal to laminations but each at a right angle to each other. Extra photos of polished areas will be helpful to send. Consider finding someone that can take photos with a microscope since the small details will help

Kershaw determine what this is.

 

Let us see your photos and read Kershaw's comments.

 

[Hank]

I cut and polished the specimen as you can see in the attached photos; I sent the photos to Mr. Kershaw for further review.  He responded tonight by email as follows:

 

Dear Hank,

 

Thanks for your efforts to get better pictures. I can see from the photos that this sample is badly recrystallised, and a lot of the structure is altered. I am pretty sure it is a stromatoporoid, I can see in some of the photos the indication of laminae and pillars. However, it is not a well-preserved sample, it has lost a lot of its original structural features. You can see the central region has a cavity lined by crystals, and there is partial formation of crystal-lined cavities in many places in the sample. It is a pity, but it happens often with stromatoporoids that their structure is altered badly.

 

I hope this is helpful.

 

Are you able to tell me the geological age of the specimen?

 

 

Best wishes

Steve

 

I really appreciate the thoughtful opinions everyone provided.  This forum and the people here are a treasure.  I have no depth of knowledge in this arena, thank you all for sharing yours.  Now, if you wouldn't mind, how would I determine the geological age of the specimen?  I have looked for geological maps of the area, but apparently I don't know what to look for.  This was found about two miles north of Golden Shores, Arizona, is there a method to determining the age based on the location and the type of specimen?

[Malone]

Very neat! It looks like the pillars or columns kind of meander more than  the pictures I saw on the internet. I hope you continue to find as much information as possible, age,names, defined characteristics, etc. thank you for sharing this with me! I have learned very cool stuff in the course of investigating your specimen. To think this could have been one the earliest sources of oxygen. One of the earliest forms of life. It would be neat to examine it microscopically and see if there's fossilized critters in there. I don't know enough about microscopy to know what magnitude of magnification they would be visible.

[DPS Ammonite]

Thanks for sending these photos to Kershaw. And thanks to professionals such as Kershaw that are willing to work with amateurs to help them ID their fossils in the name of public education. 

 

We we can make some

educated guess as to where this came from. If this came from old Colorado River terrace deposits, look to the source of most of the rocks: the Grand Canyon. 

The Mississippian Redwall Limestone has stromatoporoids as does the Devonian Temple Butte Limestone. 

 

There is also the possibility that this came from nearby Devonian and Mississippian formations and not from the erosion of the Grand Canyon. A look at an Arizona geological map may provide clues of the fossil origin.  https://www.google.com/amp/s/www.theatlantic.com/amp/article/558797/

 

 

[KCMOfossil]

Nice job with the pictures.

[Hank]

Thanks, I had to make do with what I had, an Iphone and a 10x/20x lighted eye loupe.