Nah. There are all sorts of ways to suspend glass microparticles and a binder in some kind of solvent that evaporates after spraying, leaving a glass-particle-a

Nah. There are all sorts of ways to suspend glass microparticles and a binder in some kind of solvent that evaporates after spraying, leaving a glass-particle-and-binder layer behind. The physics/chemistry of it are pretty easy (for those so inclined). What's probably hard is making the deposited layer durable and non-toxic. For example, if the glass microparticles turn into aerosolized dust then you probably don't want to do a lot of breathing anywhere nearby; think asbestos and cigarettes.