Why is pumice an igneous rock?

Answer 1

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.

Answer 2

Pumice is a type of extrusive volcanic rock, produced when lava with a very high content of water and gases (together these are called volatiles) is extruded (or thrown out of) a volcano. As the gas bubbles escape from the lava, it becomes frothy. When this lava cools and hardens, the result is a very light rock material filled with tiny bubbles of gas. Pumice is the only rock that floats on water, although it will eventually become waterlogged and sink. It is usually light-colored, indicating that it is a volcanic rock high in silica content and low in iron and magnesium, a type usually classed as rhyolite. If the lava hardens quickly with few volatiles, the resulting rock is volcanic glass, or obsidian. Pumice and obsidian are often found together.In commerce, pumice is the term applied to larger pumice stones, whilepumicite consists of fine grains or ash. Pozzolan is a fine-grained pumicious material (both natural and man-made), which combines with lime to make a smooth, plaster-like cement. These three similar materials may be found and mined together, but they have different characteristics and different uses.The name pumice is derived from the Latin word pumex, meaning foam.
Source:Mineral Information Institute

Answer 3

near a volcano