Sources: MIT Review, CNN [Corning Response]
quote: Now scientists have learned to grow transparent sapphires and could soon use the lab-made stones to form smartphone screens.
quote: Sapphire is the world's second hardest material, and is tougher than even the strongest Gorilla Glass
quote: make large enough sheets for large phone screens may be new
quote: [If anyone reading this has worked with semiconductor sapphire substrates and could chime in as to how easy/difficult it was to cleave that would be appreciated]