Burnt Cretaceous wood

[Creek - Don]

Hello everyone again.  About a month ago, while I was fossil hunting in local Dallas creek, I came across what looked like a prehistoric burnt wood that has been exposed by creek water.   When I looked at it, other half of the wood was missing and washed away.  Other half was embedded into a rock as you can see on the picture,  part of the wood was petrified and other half was in carbonized form.  It smelt like sulfur / burnt wood.   I dug it out and kept the wood in my collection, but some still remains in the limestone.    It was very strange that single burnt fossilized log was embedded in the limestone layer and petrified like that. Has anybody seen something like this?  

[grandpa]

I have a specimen very similar to your description that I found in a Rio Grande River gravel pit Eagle Pass (Cretaceous I think).  What I believe you've found is fossilized wood, part of which was mineralized (petrified) and part of which was preserved in the carbonized form of coal.  At least that's what I've determined I have, which again sounds a lot like what you are describing.

[DPS Ammonite]

It looks like carbonized/ coalified wood. I see lots of iron staining around the wood. Do you see pyrite in the wood? I have found in the Austin Chalk, carbonized wood that was partially replaced by pyrite.

[Creek - Don]

Yes, thanks for that info grandpa.   I thought that was burnt wood, but turned to coal after buried so long.  DPS, yes, I did see the metal type of substance on the wood, could been the  hematite or pyrite embedded /covered some part of the wood.  Some of the wood pieces  were so light as if just burnt yesterday.