Flashed glass

Refers to a type of glass characterized by two or more layers of color, usually a thin layer or "flash" of colored glass layered on a clear or light-colored glass. It is created by dipping a small blob of dark glass into a pot of light-colored glass, and then blowing the blob into a bubble in which the distinct layers are formed. It is used to make stained glass, and is valued over "pot-metal glass" for certain effects, because the thinner layer of color allows more light to pass through the window, while the saturated color of pot-metal glass results in a darker interior.