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This report sets out the results of a study on the efficiency and feasability of 1064 nm pulsed laser cleaning of gilding on wooden supports, and the conditions for optimizing laser parameters have also been analyzed. Sixty 4 cm x 4 cm test samples of gilding on wood were especially created for this study, simulating different types of gilding and protectives. Laser cleaning was assessed on different samples og gilding layered with virgin wax deposits, paraffin wax deposits and dust deposits. The nd-YAG laser clean-ing on gilding has not been effective ither for removing waxes, neither virgin nor paraffin, nor the dust dirt simulated in this project.

The removal of unwanted matter from surface stones is a demanding task in the conservation of cultural heritage. This paper investigates the effectiveness of near-infrared (IR) and ultraviolet (UV) laser pulses for the cleaning of surface deposits, iron oxide stains and different types of graffiti (black, red and green sprays and markers, and black cutting-edge ink) on dolomitic white marble. The performance of the laser techniques is compared to common cleaning methods on the same samples, namely pressurized water and chemical treatments. The degree of cleaning achieved with each technique is assessed by means of colorimetric measurements and X-ray microfluorescence. Eventual morphological changes induced on the marble substrate are monitored with optical and electronic microscopy. It is found that UV pulsed laser ablation at 266 nm manages to clean all the stains except the cutting-edge ink, although some degree of surface erosion is produced. The IR laser pulses at 1064 nm can remove surface deposits and black spray acceptably, but a yellowing is observed on the stone surface after treatment. An economic evaluation shows that pulsed laser cleaning techniques are advantageous for the rapid cleaning of small or inaccessible surface areas, although their extensive application becomes expensive due to the long operating times required.