Distinctive features:  
White or creamy white high vesicular rock, but weathers to a pale brown on its surface. Very low density.

Colour: 
Creamy white when fresh, but turn pale brown on surface when weathere.

Texture and granularity: 
Vesicular.

Composition: 
Composed principally of glass froth of granitic to granodioritic composition.

Field associations: 
Chiefly on rhyolitic to dacitic volcanoed.

 

 

Worldwide.

 

Abrasive, cleansing powders.