HERCULES

[LEICESTERSHI]

Straighforward puzzle except 9A Sedimentary clay or mud rock, readily splits into thin layers. Could one argue for both SHALE and SLATE?

[squarebear]

I would think slate fits the clue better than shale which is mostly loose rocks and stones found near a beach/river.

[LEICESTERSHI]

Thanks squarebear - love the name!

[Davao]

SHALE is a sedimentary rock from clay. SLATE is Metamorphic. I would therefor go for SHALE

[08012006]

"Shale is a fine-grained, clastic sedimentary rock composed of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. Shale is characterized by thin laminae or parallel layering or bedding less than one centimeter in thickness." I'd go for this as the answer to 9a

[dwil]

I don't think all that will fit! LOL