"That’s what happened to scientists at Cornell University and Germany’s University of Ulm when they discovered the world’s thinnest sheet of glass while attempting to make graphene. They noticed what they called “muck” on the substance they were attempting to create, so they took a closer look. That look revealed something that wasn’t supposed to be there, something that had never before existed (at least, not to our knowledge). But thanks to a small air leak in their equipment, there was glass — glass that’s two atoms thick, making it the thinnest glass known to man."