Extensive analyses of outdoor bronzes in Augsburg and Nuremberg (both in Western Germany) have shown that the methodical starting point for determining corrosion products on this type of bronze must be improved. X-ray diffractometric analyses provide an extensive spectrum of inorganic copper, lead, and calcium compounds, some of which are already known and others which have not been described until now. Additionally, investigations using gas chromatography/mass spectrometry allow the identification of various metal soaps and other purely organic products. With the help of these results it is possible to identify both older and younger protective coatings. A warning can be derived from the presence of copper soaps (i.e. copper salts of fatty acids) against the use of waxes and oils which are not acid-free.