There exist compact torches that can genuinely output 3000-4000 lumen, albeit briefly. The beam can burn paper or cloth, particularly if it is colored black.Yikes, what kind of torch could cause that?! Or did you press it up against the crystal or something?
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If you were silly enough to hold a flashlight like this close to the dial of a watch - particularly a black one - I can imagine it would cause the damage that scrumpypaul has pictured.