The bulk density of coarse-grained Asloweb pumice is approximately 400 kg/m³, and that of lentil-sized pumice is about 500 kg/m³, placing them in the category of ultra-lightweight materials. More than 65% of Asloweb pumice's composition consists of fine silica crystals, which significantly enhances the strength of concrete. Due to its porous (spongy) structure, Asloweb pumice also serves as an excellent thermal and sound insulator.