Perlite is a vitreous rock formed by the rapid cooling of acidic lava erupted by volcanoes and is a special variety of acidic volcanic eruptive rocks. Perlite is named for the presence of spherules or a large number of pearl-like cracks in the acidic volcanic glass matrix. In the petrological classification of magmatic rocks, it belongs to the granite-rhyolite (acidic rock) type and vitreous rhyolite. In the structural-functional classification of mineral raw materials in mineral material science, perlite belongs to the three-dimensional structural rock category and the functional rock subcategory.