What is perlite used for?

Perlite is mainly used in construction products, such as ceiling tiles, roof insulation products, pipe insulation and the filling for masonry brick construction. It is also used as building insulation.

Perlite is a volcanic glass that becomes porous and expands when it is heated. According to MInerals Education Coalition, perlite is capable of expanding up to 20 times its original volume when heated. Volcanic glasses such as perlite are formed when molten rock flows out of a volcano and cools quickly. Perlite is usually gray, but it can also be green, brown, blue or red before expansion. After expansion, perlite is usually light gray or white.