`  # Ah .. wrong term, luminescent is probably not the right term (or another property), the experiment describes thermochromism. # See point 4 ..  # 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 2)... :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 .. ?    `