Granite

Granite was a type of stone.

Earth's crust was made of granite, formed out of the volcanic eruptions in the planet's early history. (AUDIO: Exploration Earth)

Peladon was rich in granite, but had no chalk. (PROSE: Legacy)

The Zeld were capable of creating flying saucers which could fly through solid granite. (PROSE: The Ghouls of Grestonspey)

Leela once referred to Aberdeen as the "granite city", and the Fourth Doctor noted that in fact the granite emitted more radiation into the bodies of the residents of Aberdeen than would a nuclear power plant into its workers. (TV: Underworld)

A granite slab was part of the invisible lift entrance to Torchwood Three. (TV: Everything Changes)