How to use "slate" in a sentence

As a sponge soaked up water, she took a chill from the surface of the slate

Two words were printed on the slate:

Snatching up the felt eraser, she vigorously wiped the slate clean.

Two hundred yards away, at the far side of the concrete field, stood a one-story windowless building, approximately a hundred feet long, with a steeply pitched slate roof.