The Romans invented glass mirrors (before they were just smooth metal surfaces). Adding glass to a sheet of metal, allows to protect the metal from corrosion and scratches and, at the same time, to reduce the thickness of the metal to a minimum.
The Romans invented glass mirrors (before they were just smooth metal surfaces). Adding glass to a sheet of metal, allows to protect the metal from corrosion and scratches and, at the same time, to reduce the thickness of the metal to a minimum.