In 2000 the Getty Conservation Institute (GCI), began collecting and analyzing all photographic material used during the era of so-called chemical or classical photography. The main focus was on all different types of photographic paper used to produce photographic images that are now in museums and archives. Analysis of photographic papers donated to the GCI by the Gevaert Company were recently added to the GCI database and the specific results of their analysis showed significant differences in paper composition between various years. The compilation of our analytical data has shown a broad variation in chemical composition between photographic papers produced by different manufacturing companies during different years. These variations in composition between different papers can provide a basis for the scientifically based provenance studies of photographic paper and actual photographs.