Perlite is a generic term for naturally occurring siliceous rock and not a trade name.
The distinguishing feature which sets Perlite aside from the other volcanic glasses is that when heated to a suitable point, it expands from 4 to 20 times its original volume. This expansion is due to the presence of 2 to 6% combined water in the crude Perlite rock. When quickly heated to above 871 °C (1600 °F), the crude rock pops, as the combined water vaporizes which accounts for the amazing light weight and other exceptional physical properties of expanded Perlite.
This expansion process gives also to the expanded perlite one of its distinctive characteristics, its white colour. While the colour of the crude rock ranges from transparent light grey to glossy black, the colour of the expanded perlite ranges from snowy white to greyish white.
Since Perlite is a form of natural glass it is classified as chemically inert, with a pH of approximately 7.
Perlite is a 100% ecologically clean material. There are many ways to use perlite but its main application is in construction.
Due to its exceptional thermal insulation characteristics as well as its light weight perlite is widely used in thermal insulation products in the construction industry.
Along with its thermal insulation properties, perlite improves not only the fire protection but also the soundproofing. When using perlite rock in the production of building materials, the finished product is light, fire resistant, and has extremely high thermal insulation properties, which makes it perfect for roof slabs, partition and external walls of high degree of fire resistance, areas of high humidity, and many other uses. Perlite allows walls to breathe and creates a natural microclimate, does not cause any allergies and keeps its unique properties for an unlimited period of time.