Ah  wrong term luminescent is probably not the right term or another property the experiment describes thermochromism  See point     I think it is used in some ointments indeed Calamine is maybe a spam    If it is in a sunblock and you apply it to your body it should block absorb UVA and UVB right  But indeed if it is then light sensitive point  For the last two points Sunscreen does say that zinc oxide is one of the active components  So that sounds right to me except  light sensitive  hmmm  What this article def could use are a handful of  tags or maybe even an   I would not call it disputed but an eye of chemist in the field of solar cells may also be a good idea