"Perlite" Natural Recordings by Native Speakers
Perlite is a type of volcanic glass that is used as a lightweight aggregate in construction materials, such as building insulation, and also as a soil amendment in horticulture. It is created when obsidian lava is rapidly cooled, which causes it to expand like popcorn and form a lightweight, porous, and inert material. Perlite is often used to improve soil drainage and aeration, increase water retention, and reduce soil compaction. It is also used as a substrate in hydroponic systems and as an additive in some types of concrete.