A light, porous type of pyroclasticigneous rock, formed during explosive volcanic eruptions when liquid lava is ejected into the air as a froth containing masses of gas bubbles. As the lava solidifies, the bubbles are frozen into the rock.
The wind blew close to the ground - it rooted among the tussock grass - slithered along the road, so that the white pumice dust swirled in our faces - settled and sifted over us and was like a dry-skin itching for growth on our bodies.