Frosted glass is glass that is made opaque through a process that roughens or blurs the surface of the glass. Acid etched glass uses abrasives to create a frosted glass appearance. Acid treatment is used to make acid-etched glass. This glass has a matte surface finish on one or both surfaces of the glass surface and is suitable for shower doors, glass partitions and more. The surface of frosted glass will be uneven and slightly thinner, so frosted glass cannot be used as a mirror.