ID my weird stegasurous bony plate ?

[George Nelson]

I found this flat plate fossil in a creek bed on my ranch in SW Texas (Texas hill country, Uvalde co., Fush creek, DRY FRIO river valley). It is c. 9x4 inches by c. 1 inch thick. It seems to be a key stone shape, with a bony porous  

inside, covered with a "skin" ( thin as a sheet of paper) with wild complex  patterns of streaks and dots on both sides. The "skin" is worn away on the edges , showing the inside porous

core. There is a damaged or perhaps an attachment scar on one side. There seem to be some structure inside the core ( veins ?, or spines ?) . at one end, a tip has a red stain in the pores.

When I first found it in gravels, I picked it up because I thought it was just a flagstone with a interesting pattern , caused by thin layers of (limestone?) that had been weathered into

the swirling patterns. I forgot about it till 6 months ago, looked close and noted the porous bony core, and that the swirling patterns were not weathering at all.  I am guessing it might be a stegasorus plate with skin  and the patterns maybe decoration or some type of id marking or cooling feature. Or something else completely.But, I need some input as to what it may really be. 

[Troodon]

Welcome to the forum 

Sorry not a Stegosaurus plate its geologic 

 

Here is a real plate, very thin

 

 

[George Nelson]

I totally thought that when I found it, BUT, It has a porous core ( sticks to my tongue) , and under magnification it has organic like textures (veins, dense spots  in edge ) and the edges are worn down through the "skin". There are various types of plate shapes on back plates around the world, this thing has a very thin tip.. I have no idea what is , but it seem to be very well preserved, to have the thin skin surface cover a bony plate. I thought at first it was just made up of thin layers , worn down by uneven wear to have a topo map design of contours. But that is not how it is made. The skin patterns are very detailed. I am an agnostic about it , but after close study no not think it formed

by geologic formed by nature action. It is weird. I am a retired museum exhibit preparator and worked at the Texas Memorial Museum at UT Austin, I have worked on 

mounting and repairing dino bones and have seen and handled bones a bit : but this stumps me.

 

[JohnJ]

Hi George, do you have images of the other side and close ups of the porous layer? 

[abyssunder]

I see very nice Liesegang rings there. https://en.wikipedia.org/wiki/Liesegang_rings_(geology)

[abyssunder]

https://www.google.com/search?q=liesegang+rings+geology&biw=1360&bih=612&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjpzKag5bHPAhWI7RQKHU4WDIMQ_AUICSgC

[Ptychodus04]

According to the San Antonio sheet of the Geologic Atlas of Texas, the site you are searching is either Devils River Limestone or Glen Rose Limestone. Both are Cretaceous marine deposits but of course, dino material is possible from the Glen Rose. Definitely no chance of a Stegosaurus though.

 

That being said, your piece is pretty clearly geologic in nature.

[George Nelson]

There is a dinosaur track way ( 3 toes, other track ways in general area) in a near by dry creek bed c. 1 mile west of the find site of this object. So, the area was a near shore dinosaur habitat at sometime.

I will post other side and another detail of tip edge showing pores in core ( there is a detail photo posted above of pores with red stain: please enlarge image).

[JohnJ]

As others have mentioned, this is geologic in origin.  It's not uncommon to have harder layers intermingled in sandstone bedding.  Those layers do get "drilled" by various tiny invertebrates, or become porous as result of the chemical dissolution of some minerals.  It can look like cancellous bone, but it isn't.  You've probably spent time at some parts along the Texas coast and seen examples of highly perforated (bored) clay.  Picture some of those pieces sandwiched between storm deposits of sand. 

 

 

[siteseer]

The thing that doesn't show well in Troodon's photo is the texture of the flat sides of the plate - kind of a rough channeled texture from blood vessels running through it.  Stegosaur plates are extremely rare - tend to bust up.  Even Stegosaurus teeth are very rare.  We get the idea they are at least as common as any other dinosaur of that time but you just don't see that much from that animal.