New bad hc: Elves are resistant to mercury. As in they can literally consume it and theyāll be pretty fine other than mild sickness, because yknow. Itās not meant for consumption, but it wonāt kill them and knowing them they eat it as like. Red chilli or something. Thatās why theyāre all glowy.
Either that or they naturally emit UV light. Or something.
Like the trees of Valinor had insane levels of UV that was so strong the elves of Aman absorbed it. At least Laurelin did. Because the sun emits UV rays. So it makes sense the tree did tooā¦ or was it just the fruit? Did they eat the fruit in like. Festivals or something?? Is that why they glow??? Did it give them some level of immunity to sunburn and the like????
Even worse Hc: the Silmarils through the processes of creation and meshing of light, are radioactive. They cause slow radiation poisoning that drives elves mad. And it gets worse with every new generation born in Arda as they lack the heightened resistant Valinor born elves had. (Though that erodes after years of no exposure.)
Which is why FĆ«anor started to really go off the deep end as he wore the Silmarils more and more. And by proximity, his kids slowly did too, but it was slow onset.
