Pumice: The Floating Volcanic Rock

Pumice is a volcanic rock that floats on water for years.

Pumice forms when super-heated rock shoots out of volcanoes.

Pumice is volcanic glass filled with tiny bubbles called vesicles.

Pumice colors vary from white and cream to brown and black.

Black pumice contains tiny magnetite crystals causing its color.

Tube pumice contains long, tubular bubbles that look like wood.

Pumice porosity ranges from 64 to 85 percent by volume.

Pumice rafts float on oceans and travel hundreds of kilometers.

Powdered pumice called pumicite consists of particles under 4 millimeters.

Pumice rafts support marine life as they drift across oceans.

Pumice’s bubbly texture and lightness make it a unique stone.