What does it mean when an art dealer says,a painting has been tested with a blac

Question:

What does it mean when an art dealer says,a painting has been tested with a black-light?

Best Answer - Chosen by Asker: A blacklight is a great tool to use when inspecting antiques and collectables. It can detect repairs, flaws, cracks and paintovers. The blacklight will show restored or touched up areas on an antique painting. It does not work for detecting forgeries. An old forgery will look the same under a black light as will and old original.