UV radiation reacts and gives fluorescence with specific compounds of the surface of an artwork.
For a painting, this approach highlights the superficial varnish which changes in fluorescence intensity reveal, in particular, areas of repaint and restoration. It is also possible to distinguish different natures of pigment according to the color of their fluorescence.
For other types of objects of art, observation under UV may allow visualization of sticking zones. It might be then, useful to use it in case of sculptures presenting restoration areas
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