Petrified wood encased in segmented clay(?) ID needed

[SamiCG]

This was found on the banks of a river bed around Locust Fork River in Blount County Alabama

[Rockwood]

Not really petrified wood, but definitely a plant fossil. It appears to be either a pith cast, or an external mold, in a really cool looking concretion.

[LabRatKing]

Wow. Very cool specimen!

[Kato]

Indeed a neat find! I occasionally find similar appearing concretions but never with a fossil!

[SamiCG]

2 hours ago, Rockwood said:

Not really petrified wood, but definitely a plant fossil. It appears to be either a pith cast, or an external mold, in a really cool looking concretion.

Thank you Rockwood!!

[FranzBernhard]

Nice specimen, indeed.

The concretion itself is an ironstone concretion, mainly composed of the iron mineral siderite (FeCO₃). This mineral weathers / oxidizes to brown iron hydroxides ("limonite", roughly FeO(OH)) or red iron oxide (hematite, Fe₂O₃). Typical and indicative for siderite concretions is the conchoidal spalling due to volume loss during weathering.

Franz Bernhard

[SamiCG]

11 hours ago, FranzBernhard said:

Nice specimen, indeed.

The concretion itself is an ironstone concretion, mainly composed of the iron mineral siderite (FeCO₃). This mineral weathers / oxidizes to brown iron hydroxides ("limonite", roughly FeO(OH)) or red iron oxide (hematite, Fe₂O₃). Typical and indicative for siderite concretions is the conchoidal spalling due to volume loss during weathering.

Franz Bernhard

FranzBernhard, I appreciate this immensely.  This explanation is much more informative than it looks. I love learning this way. ☺️

[SamiCG]

Thank you so much to all who have responded thus far. So much easier to learn as an adult sometimes. ☺️ My rock hound has been collecting rocks since he had pants with pockets and I have always wanted to log and confirm best I can to make him a proper collection or get close to it. You all are informative so much so I don’t need a geology degree to understand and I truly appreciate that. I love the hunt I have been on these last couple days. Your responses have lead me on some fascinating information.  I am so glad I found this forum. 

[FranzBernhard]

9 hours ago, SamiCG said:

Thank you so much to all who have responded thus far. So much easier to learn as an adult sometimes. ☺️ My rock hound has been collecting rocks since he had pants with pockets and I have always wanted to log and confirm best I can to make him a proper collection or get close to it. You all are informative so much so I don’t need a geology degree to understand and I truly appreciate that. I love the hunt I have been on these last couple days. Your responses have lead me on some fascinating information.  I am so glad I found this forum. 

Your comment is highly appreciated, thank you!

Franz Bernhard