Abstract: There is disclosed a process for strengthening a glass article. This process comprises the steps of: 1. providing a glass article comprised of from about 1 to about 30 weight percent of at least one compound of a first monovalent exchangable cation, 2. coating the surface of said glass article with a source of a second exchangable cation which has an atomic radius larger than that of the first exchangable cation, and thereafter 3. subjecting said coated glass article to a source of microwave radiation at a frequency of from about 0.9 to about 22.1 Gigaherz.