Is it real

[Matt3030]

I found this in San Antonio TX within the ground at about 4 inches deep. It looks like a claw of some sort and maybe reptile leg, or arm?  Any thoughts?

[Lone Hunter]

I think this is chert which can have interesting shapes,  and this probably should be moved to Fossil ID to make sure.  @DPS Ammonite

[DPS Ammonite]

I don’t see a fossil or claw. We need to wait for the real vertebrate experts to chime in.

[RJB]

All I see is a rock

 

RB

[Rockwood]

I sure don't qualify as a vertebrate expert, but I don't see the texture of bone here either.

[digit]

5 hours ago, Matt3030 said:

It looks like a claw of some sort and maybe reptile leg, or arm?

 

Welcome to the forum!

 

Interestingly shaped rock for sure--definitely one that calls to be picked up and inspected closer. The porous texture is not the same as would be found inside bones and more likely indicates that this is a sedimentary rock. Fossils are most often found IN sedimentary rocks but sedimentary rocks are not themselves fossils. Looks to be a rock that at some point was tumbled to this smooth irregular shape by water (ancient river, stream or lake). No indications that this could be any reptilian appendage--that would require bone texture and several articulated arm/leg bones to be visible. Those new to fossils can often imagine that animals (or parts of animals) can be preserved not only articulated but with flesh and skin when they see a shape that reminds them of a part of a live animal. Fossilization just does not work this way and any apparent similarities in shape and form are merely coincidental.

 

https://txpub.usgs.gov/txgeology/

 

You might find this online resource to be valuable in determining the age of the surface deposits in your area. The map can be zoomed and scrolled so you should be able to zoom into the area in which you found this rock to get an idea of the age of the rocks near the surface. Click on a point to see a description of what formation lies exposed there. The area around San Antonio looks quite complex and interesting geologically. There also seem to be some elevation and a lot of erosional features which could explain the tumbled and smoothed shape of your item.

 

 

Cheers.

 

-Ken

 

 

[TOM BUCKLEY]

2 hours ago, digit said:

The porous texture is not the same as would be found inside bones and more likely indicates that this is a sedimentary rock.

Ken,

What is it about the texture that points to it not being a bone. Doesn't the porous nature of the cavities point to what one would find in a bone?

Tom

[Rockwood]

1 hour ago, TOM BUCKLEY said:

Ken,

What is it about the texture that points to it not being a bone. Doesn't the porous nature of the cavities point to what one would find in a bone?

Tom

In this case it's more the distribution of the pores that is off. 

[digit]

Indeed. Both size distribution as well as location.

 

One would expect smoother cortex bone on the outside and more evenly spongy cancellous bone on the inside. The irregular sized pitting all over the surface is much more in line with a granular sedimentary rock with particles eroded out. I did have to review the fifth image several times as that one shows the most bone-line of textures. The shape is also quite improbable for a bone--even for tympanic bullae or periotics which can be quite lumpy and irregular.

 

 

Cheers.

 

-Ken

[JohnJ]

It might be a piece of karstic tufa.

[digit]

That would certainly explain the bubbly texture. You are certainly much more familiar with the fossils and the formations of Texas.

 

 

Cheers.

 

-Ken

[TOM BUCKLEY]

1 hour ago, JohnJ said:

It might be a piece of karstic tufa.

 

Caustic tofu? 

[digit]

Yup. I'm guessing that would look similar.

 

 

Cheers.

 

-Ken

[Mark Kmiecik]

I can see the part that looks like a leg and toe bones. One very important feature of those bones is not present. There is no indication of joints between those bones. Also, as others have stated, the pores that one would normally see in bone are of the wrong size, in the wrong places and not in a pattern that would indicate bone.