Perlite | Natural Glass Insulation, Horticulture Construction
Perlite has a waxy to pearly lustre and is commonly gray or greenish but may be brown, blue, or red. Some perlites are of intrusive. Perlite, a natural glass with concentric cracks such that the rock breaks into small pearllike bodies. It is formed by the rapid cooling of viscous lava or magma. Perlite has a waxy to pearly lustre and is ...