happeline vulkaaniline klaas, poorsus 30-40%. Kuumutamisel perliit puhetub (maht suurened kuni 20 korda) ja moodustub kerge poorne puistmaterjal, mida kasut. betooni ja krohvisegude täitematerjalina ja soojustusmaterjalina.
a form of siliceous lava that is characterized by many spherical and convoluted cracks.When heated to 720-1090 degrees C it expands to 10-20 times its initial volume.
an acid and glassy ingenous rock which exhibits perlitic structure