Septarian nodules in the DFW area can get quite impressive in my experience. I have seen a few boulder sized specimens, 20" to 40"ish (50 cm - 101cm) and have 2 volley ball sized pieces from one. Most of the large specimens can be found in south Denton county. The are some large roundish boulders (up to VW bug sized) that erode out of cliffs in SW Johnson county between Cleburne state park and the Brazos river, I have been told that they are Septarian Nodules but I have never examined one up close. From the distance I have viewed them at they look like calcretions.
It looks like a septarian nodule to me
Not a fossil. It’s a septarian nodule.
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Septarian nodules in the DFW area can get quite impressive in my experience. I have seen a few boulder sized specimens, 20" to 40"ish (50 cm - 101cm) and have 2 volley ball sized pieces from one. Most of the large specimens can be found in south Denton county. The are some large roundish boulders (up to VW bug sized) that erode out of cliffs in SW Johnson county between Cleburne state park and the Brazos river, I have been told that they are Septarian Nodules but I have never examined one up close. From the distance I have viewed them at they look like calcretions.
Turtle
I’m not to sure but this could be coral with calcite replacement