Please help identify

[Hank]

Is this possibly stromatolites?  Found just north of Golden Shores, Arizona, in a dry wash in loose material on the bank of the wash.  Thank you for any help, very new to collecting fossils.

[Pemphix]

My first guess would be "no fossil", just geology.

But let's see what the experts will tell...

[ynot]

Welcome to TFF!

My first impression is yes it is a stromatolite.

But there are a lot of sedimentary rocks in that area that can look like stromatolite.

Wait for more opinions on this one.

[GeschWhat]

My first thought was stromatolite as well, but not my area of expertise. Welcome to the forum!

[Kane]

Welcome to the forum.  

 

It could be a stromatolite, but perhaps it will help identification if you tell us about the size of the specimen. 

[Hank]

It is 6" long about 2 1/2 - 3" wide, potato shaped, weighs about 1 1/2 pounds.

[Jaimin013]

Looks like stromatolites but I am not in an expect in them so hopefully someone with knowledge on this will help you. Welcome to the forum!

[abyssunder]

It could be a stromatoporoid.

[Malone]

The lines seem too thick for stromatolites but I am definitely not an expert! The ones I have seen and found have very thin lines/layers. I didn't even know what a stromatolite was until someone on the forum told me probably a month or two ago!

[Malone]

I think abyssunder has the right idea.

[DPS Ammonite]

1 hour ago, Malone said:

I think abyssunder has the right idea.

 

Malone and Abyssunder might be right. The features of the top of the colony might help with an ID.

[Hank]

Would I see evidence of mamelons if this is a stromatoporoid?  If so would they be on either end?

[DPS Ammonite]

You beat me to it Hank. You might see mamelons if this is a stromatoporoid. See if you can give us a photo of the top of the colony. Stromatolites are nearly featureless on top while stromatoporoids have regular repeating features similar to bryozoan or sponges.

[Hank]

Here are photos of both ends.

[DPS Ammonite]

The photos are not clear enough for me to say that I see regular repeating features that are associated with stromatoporoids. I will say that they are likely stromatolites unless you can see diagnostic features that the photos do not show us.

[Hank]

There is only one small area on the end that may be of interest.

[Hank]

Thank you all very much, I appreciate your observations.

[Malone]

I found this on the internet. It looks like everyone could be right.

[Malone]

lol except me! Cause I texted that I thought it too thick for stromatolites. Oh well.

[Malone]

By the way creative photography props!

[Rockwood]

46 minutes ago, Malone said:

lol except me! Cause I texted that I thought it too thick for stromatolites. Oh well.

Count the lamina per cm in the example and scale it to the 6" of the post.

I'm with your first thought.

Kind of makes stromatoporoid a long shot to.

[abyssunder]

If the specimen has laminae and pillars it's a stromatoporoid.

[Hank]

Here are a couple with a scale alongside.

[Rockwood]

Guess maybe I was paying too much attention to the gaps.

[DPS Ammonite]

Here is the best online reference to tell the difference between stromatolites and stromatoporoids from Dr. Steve Kershaw. I suggest the original poster send a picture of it to Steve.  (Let us know what he says.)  stephen.kershaw@brunel.ac.uk Sometimes you need a lens or microscope to tell the difference: 

 

http://www.earthsurfaceprocesses.com/3f-E-StromatolitesStromatoporoids.html