It's why he's so vague and pops up in improbably locations and pretends he's got meetings all the time! XD

Now we know the truth! :D

I don't know - something at least a bit toxic as well, I should think. But bright and shiny and useful!

Maybe not a "proper" Element (we know it's allowed in canon, haha) so it could be a gem like Emerald, which is shiny and kind of toxic? Or lapislazuli? Yes... I also can't see them as elements exactly as they are in canon, but the AU is fun to think about, hehe.