Post-Columbian America is obviously the superior place to post.
Too narrow an area!
Meanwhile, you might wonder, what is my interest in UV/"black" lights?
Not only can one mark an item with an invisible UV pen to prevent buyers of antiquities from getting away with swapping your better widget with their inferior widget and claiming you sent them crap, they are also handy when doing cache hunting in and around houses. With an UV lamp one can find alterations in walls, floors, fireplaces and so forth.
In addition, they can be used to find repairs, anomalies, in paintings and other objects.
A must have in the TH'ers toolkit.