One. Scientific Foundations of Hollow Glass Microspheres 1.1 Composition and Microstructure one.1.one Chemical Composition: Borosilicate Dominance Hollow glass microspheres (HGMs) are mainly made up of borosilicate glass, a fabric renowned for its lower thermal growth coefficient and chemical inertness. The chemical make-up ordinarily consists of silica (SiO₂, fifty-90%), alumina (Al₂O₃, https://www.dostally.com/post/345006_elementary-substance-is-a-pure-chemical-substance-that-consists-of-atoms-belongi.html