Oogneiss
Oogneiss is a rock found in the deepest and darkest depths of our real mother Earth! We're not sure what it does. No information on its structure. It could be a new element or something, but really we just don't gosh darn know. I'm sorry. But we're really good at coming up with stories to explain things, right? Here we go!! In the beginning, there was... darkness... and then... I made light?? Haha, I don't know what I'm doing, man...
Instructions
Don't drop this in bodies of water. Don't put this near placental mammals. Don't bring this to the UN. Don't look at this. Don't forget to drink your water. Don't put this *in* the water. Don't do anything with this, for the love of God. Please don't try to get energy from it.
Lenses made of oogneiss are found to be able to focus light in such a manner that every physically imperceptible flaw in a specimen is magnified exponentially: Glass shatters in an instant, baby seals are freed from their murderous instincts, and Earth's society is in ruins, among other things.
If the oogneiss begins to unfurl chaos from its molecular roots, look directly into its eyes. It cannot stand the intimidation of a sustained gaze. In fact, we have a guy whose job it is to look this thing in the eyes day in and day out - sometimes he blinks, and that's a thing or two. Remember the dinosaurs?