Dan Frommer of Quartz:
The story of Apple’s now-bankrupt sapphire venture in Arizona is full of drama: The Wall Street Journal’s Daisuke Wakabayashi reports at length (paywall) on some of the challenges and disappointments that Apple and its partner, GT Advanced Technologies, have dealt each other. But there’s one particularly interesting stat that explains why Apple and GTAT even bothered in the first place. Apple is already consuming “one-fourth of the world’s supply of sapphire to cover the iPhone’s camera lens and fingerprint reader,” Wakabayashi writes.
Here's Daisuke Wakabayashi's report in The Wall Street Journal (behind paywall).