(1865–1929). A native of Austria, Zsigmondy received the Nobel Prize in chemistry in 1925 for his work in the field of colloid chemistry, which was initiated by his interest in ruby glass (a colloidal gold suspension). His most important contribution to chemistry was his invention of the ultramicroscope (with Siedentopf) in 1903.See Ultramicroscope; Tyndall Effect.