Multilayer polychrome coatings on medieval and Renaissance stone artefacts represent substantial challenges in laser cleaning. Therefore, polychromic models with classical pigments, minium (P22+Pb4+O4), zinc white (ZnO), and lead white ((PbCO3)(2)center dot Pb(OH)(2)) in an acrylic binder, were irradiated with a Q-switched Nd:YAG laser emitting at 532nm. The studied medieval pigments exhibit strongly varying incubation behaviours directly correlated to their band gap energies. Higher band gaps beyond the laser photon energy of 2.3 eV require more incubative generation of defects for resonant transitions. A matching of the modification thresholds after more than four laser pulses was observed. Laser cleaning with multiple pulsing should not exceed ca. 0.05 J/cm(2) when these pigments coexist in close spatial proximity. (C) 2013 Elsevier B.V. All rights reserved.