The iPhone 6 was supposed to have a sapphire display. More than a year ago, Apple turned to GT Advanced Technologies, the now-bankrupt supplier, to solve its longstanding problems with scratched and cracked displays. But as soon as the two companies signed an agreement, their relationship became riddled with complications. In the ensuing year, as chronicled in detail by The Wall Street Journal, everything shifted. Apple originally wanted to buy furnaces with which to make sapphire itself, before changing its mind and deciding to simply buy the produced sapphire from GT. But GT couldn't make sapphire at the volume and quantity Apple wanted, and the relationship splintered over and over until it broke.

The Journal's story is full of remarkable details, like the almost-loss of 500 sapphire bricks worth hundreds of thousands of dollars. Or the 700 people GT hired as a result of the project, many of whom wound up with nothing to do at all. It's also full of what should have been obvious red flags, like the fact that three days before GT signed its deal with Apple, it produced 578 pounds of sapphire — and not one ounce was usable.

But it's fundamentally a story about the power, and the danger, that comes from working with Apple. Tim Cook and his team in Cupertino demand high quality and low prices, which make it a difficult partner to work with profitably. The prospect of making massive amounts of sapphire for the world's most valuable technology company was too hard for GT to pass up, even though its inexperience and inability to scale ultimately cost the company much more than the nearly $1 billion that was invested in the project. Apple and GT worked together to help GT stay financially solvent, but it was too late; GT filed for bankruptcy barely two weeks after the iPhone 6 was released — without a sapphire screen. In bankruptcy court, the two companies blamed each other for the failure. In truth, it seems clear both partners are to blame.

Sapphire screens are an obvious, tested improvement over the materials used in smartphone displays around the world. But if GT's story is any indication, not even Apple can find an easy way to make one of the hardest materials on earth.