With those dessication cracks it looks like this stuff formed recently, that is long after the limestone formed, and probably after the quarry operation.
DWhatley;182930 said:Kevin, does that mean drying mud (that was my first impression )?
With those dessication cracks it looks like this stuff formed recently, that is long after the limestone formed, and probably after the quarry operation.
Maybe spectral analysis could help.
Some unknown mineral in a thin shale bed that gets wet when exposed and dries in a weird way.