According to Conservation & Care of Glass Objects, written by our glass conservator here at The Museum, Steve Koob, "bright light--even ultraviolet (UV) light--by itself does not damage glass. Glasses decolorized with manganese are one notable exception because they can be solarized.
Two principle concerns regarding the control of light in the museum are (1) the buildup of heat on glass objects and (2) the overall effect of lights on temperature and humidity in the galleries. High light levels are also an issue in the case of cold-painted glasses (that is, glasses to which paint was applied after they were manufactured) and modern studio glass works that incorporate light-sensitive synthetic adhesives or natural materials."
The solarizing effect would mean the glass turns pinkish or violet in color with long exposures to UV light.
