The recent analysis of the palette used in Botticelli's Trionfo d'Amore by Raman microscopy has led to the erroneous identification of the spectrum of a degradation product, most likely that of massicot (orthorhombic PbO), as that of plattnerite (PbO 2 ) [Anal. Chim. Acta 429 (2001) 279]. The error is shown to arise from the laser-induced degradation of both the painting and a reference sample of pure PbO 2 . The spectrum of undegraded PbO 2 is presented, and the common problem of laser-induced degradation of lead pigments in art conservation studies utilising Raman microscopy is discussed.