Dino Bone or Petrified Wood? Options

[swizz]

I found this over 20yrs ago south of Denver. At the time I was working on a very large construction project. One day while I was walking around having a smoke during break I found this in the wake of an earth-mover. I had already found various sizes of petrified wood at this site and several sites nearby during heavy equipment excavations but this piece was different.
It's only a busted up piece so I doubt anyone can put the rest of the dinosaur together with it, but might be worth cabbing? It would be virtually impossible to return to the area and prospect for many reasons, the foremost being - the entire area for miles is now clustered with office buildings (Tech Ctr area).
Have a look, hopefully someone here knows how to tell if it is... or knows of a resource that might. I could be WAY off on this.

Looks like petrified wood from this side SIDE A


The other side (inside) is concave and has many brittle tube-like cavities SIDE B


Standing it on end... there are no tree-growth rings (or grain) where there should be, or anywhere on the piece


A closer look at a small exposed area of tubular cavities on the inside


A closer look at more of the exposed tubular cavities


Here is a closeup some curious raised markings on SIDE A


Any thoughts?

[CP]

Nice find Swizz, we both say petrified wood here by the looks of it.
Pic 2 shows what may have been the sectional view of a rotted fallen deadwood which then fossilized.
#4 looks like termite burrows (often in deadfalls) then also fossilized along with the tree remains.

Very typical looking of pet wood found around the State. Many times the stuff is too fractured and not solid enough for cutting and polishing but there are pieces out there that are solid enough for cutting.

Pic 3 looks like some possible agatization? On the end view some milky/gray color, you can always take a slice off and you'll soon be able to tell if it's solid or gonna' be a crumbler.
Let us know how it turns out too.

If it's a dino bone, the cross cut will be a dead give away as well showing the marrow cell cross section pattern.