In order to study the influence of urban atmospheres & particulates on the mechanism of weathering of low durability potassia-lime-silica glasses present in medieval stained glass objects, specimens were exposed in climate chambers for periods between 48-500h. Other adjustable parameters were relative humidity (RH=50,70 or 100%) & concentration of SO2 (0,0.1 or 1.1ppm) in the weathering chamber. The dust, collected near an atmospheric test site of the UN/ECE ICP-materials project, was applied to the surface of the glass samples prior to the weathering experiment. Scanning electron microscopy in combination with energy dispersive microanalysis (SEM/EDX) showed that even after an exposure of 48h a greater degree of higher weathering in the form of crystalline weathering products could be observed on those samples treated with dust compared to those without particulates on the glass surfaces.
