Hi folks.
Several years ago while digging shale with an excavator for road repair, we hit what appears (now, with forum learning) to be a concretion, typical oval/oblong shape about 5' long. We had to dig around it as it was too hard to even scratch with the machine. Over the years it has degraded to where it is quite fractured from the weathering and is easily broken up. The pic is a portion of a "ball" of densely packed fossils that was near the center of the concretion. Could this cluster have been the nucleus ?, or could it have just gotten caught up in the formation ? This is about 3 miles from my digs at home and is a much harder, blue/black shale that was at a depth of about 8'. Nice and clean ... no scrubbing necessary.
Thanks