Perlite is a naturally occurring volcanic glass that is mined and then processed to create a lightweight and porous material. It is formed by the rapid cooling and solidification of lava, which traps water molecules in its structure. When heated to high temperatures, the water molecules are released, causing the perlite to expand up to 20 times its original size.
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What is Perlite? What is its use in the garden? — amolminechem
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What is Perlite? What is its use in the garden? — amolminechem

Cosmic radiation Perlite is a naturally occurring, lightweight, and porous volcanic glass that is formed when obsidian is rapidly heated...