" There must be something in here that can drill through eight miles of
solid rock.”
He considered a hand drill, a tape measure, a corkscrew, and the iron staff we’d almost died retrieving from Geirrod’s fortress. He threw them all to the floor.
“Nothing!” he said in disgust. “Useless junk!”
Perhaps you could use your head, Hearthstone signed. That is very hard.
“Oh, don’t try to console me, Mr. Elf,” said Thor. "

― Rick Riordan , The Hammer of Thor (Magnus Chase and the Gods of Asgard, #2)