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davidcyclebackArt and antiquities experts use infrared light, with infrared light being on the other side of the light spectrum than black light and testing the material in a different way. You can do both simple and advanced tests with infrared light, from 'seeing how the material looks' to identifying the chemical makeup. You can buy an infrared viewer, though they're more expensive than black lights and not so simple to use. A total beginner can usefully use a black light, but you have to more know what you are doing to use an infrared viewer.
An expert would examine paint or whatever using both UV and IR light, each test double checking the other and picking up what the other might miss.
Interestingly, ancient manuscript historians and archeologists use infrared viewers to pick up hidden (faded away, etc) writing, so an infrared viewer might be useful in picking up removed writing on a card.
The crux of the infrared viewer and examination is that the infrared viewer allows the examiner to 'see' infrared light (normally invisible to human eyes). Different materials emit different levels of infrared light, so materials that look identical under normal daylight conditions can look distinctly different from each other under an infrared viewer. Invisible ancient writing can be read under the infrared viewer.
In fact, many art and furniture dealers use infrared viewers specifically to identify restoration. It's probable that these dealers also own a black light.
The more tests you have (black light + opacity + gloss+ infrared viewer + etc), the more likely you will identify restoration. Restoration and forgery might fool one test, but won't fool all the tests-- in particular as each test is testing a different quality. And I can almost promise you that no baseball card restorer is calibrating the infrared light emissions of his paints and glues. A university chemistry professor probably couldn't successfully do this. And if you change the infrared emissions of your paint, you probably simultaneously changed the black light fluorescence or visible color or other quality. Changing one quality changes another-- which makes it near impossible to fool all the tests in a quality series of tests.
And notice that many of the tests I included are simple ones-- opacity, gloss, etc. One of the hardest things to duplicate in a reprint or counterfeit is the gloss.