Having first differentiated the two types of lead-tin yellow by x-ray microanalysis, it was then possible to establish which type was used in various 14th-and 15th-century European paintings. In Italy it appears that type I (Pb₂SnO₄) replaced type II (PbSnO₃ during the second quarter of the 15th century. However, it has not been possible to confirm the hypothesis of a northern origin for type I, due to the lack of suitable samples. The titles and dates of more than 100 paintings prior to 1500 are listed, together with the type of lead-tin yellow used.