"The conservation of an Egyptian tomb is a delicate, painstaking process. Dirt must be removed without damaging the fragile surfaces of the walls. In some cases, the grime is attached so firmly to the surface that even conventional hand-cleaning using chemical or mechanical methods is unsuitable. Application of water or solvents can lead to further penetration of the soot particles into the surface, and the deteriorated surface may be too fragile for mechanical cleaning. This is where laser technology comes in. A group of German conservators is using an ytterbium fiber laser to conserve the 3300-year-old tomb of Neferhotep, a senior Egyptian scribe who served in the temple of the god Amun."
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