What happened to the stone?

"How could that happen?" Eric shouted desperately. "Jon had wished that the stone couldn't be destroyed." "I don't think it was destroyed," Keith replied. "It just isn't here anymore. It went somewhere else. Where, I have no idea." "What are we going to tell Jon?" "I don't know. We'll figure it out. Right now, though, I think we need to start keeping an eye on reality, making sure things don't break down too much." Eric nodded in agreement and the two left the lab and headed outside.