A donkey stamped its foot in the chalky rock.

The chalky rock breaks into plates and contains many fossils.

The drought had left no blade of grass or green leaf The chalky rocks that littered the earth were white as skulls.

Carbon dioxide is released at the surface and calcium carbonate deposited as travertine, the chalky white rock of the terraces.

If it wasn't raining like hell, it could be done with a stick in the dirt or a piece of chalky rock.

Niall observed that when he stood on a piece of chalky rock, he crushed it flat.

The track was slowly climbing now, cutting through formations of chalky rock.

The chalky rock was soft and wet, unaccustomed to so much dampness.

He removes the knife and hacks at the substance, carving out several chunks of crumbling, chalky rock, drenched in seawater.

There was an impromptu outdoor fireplace formed from several chalky rocks near the cabin, and a small pile of dry logs and sticks.