Manufactured sapphire—a material that’s used as transparent armor on military vehicles—could become cheap enough to replace the glass display covers on mobile phones. That could mean smartphone screens that don’t crack when you drop them and can’t be scratched with keys, or even by a concrete sidewalk.

Sapphire, a crystalline form of aluminum oxide, probably won’t ever be as cheap as Gorilla Glass, the durable material from Corning that’s used to make screens on iPhones and other smartphones. A Gorilla Glass display costs less than $3, while a sapphire display would cost about $30. But that could fall below $20 in a couple of years thanks to increased competition and improving technology, says Eric Virey, an analyst for the market research firm Yole Développement. And since sapphire performs better than glass, that price could make it cheap enough to compete, he says.

To read the original article: Sapphire Could Replace Gorilla Glass in the iPhone and other Smartphones | MIT Technology Review