answersLogoWhite

0

Pumice is an igneous rock because it is formed by the eruption of lava from volcanoes. The presence of the void spaces within the solidified pumice is due to thee high gas content of the lava. When the lava is erupted there is a loss of confining pressure which causes these dissolved gasses to exsolve very rapidly. This gas forms bubbles in the lava. Due to it's large surface area, the lava cools and solidifies very rapidly trapping the gas bubbles and forming the vesicular texture which allows pumice to have such a low density.

User Avatar

Wiki User

13y ago

What else can I help you with?