Back in late 2013, Apple signed a deal with a company named GT Advanced Technologies to build a sapphire manufacturing plant in Arizona. Apple would build the facility, and GT would manufacture sapphire for use in Apple's devices. Sapphire is even harder and more scratch-resistant than the Corning Gorilla Glass used in many smartphones and tablets today, and the deal gave rise to rumors that Apple would be using sapphire to protect the screens of its new iPhones.

Those rumors were repeated many times in subsequent months, though others indicated that it wasn't a sure thing. The iPhone 6 and iPhone 6 Plus ended up launching with glass screens after all. Apple still uses sapphire to protect a few important surfaces on iPhones—the camera lenses and TouchID buttons, specifically—but those components are much smaller and therefore less lucrative for their manufacturer.

GT Advanced Technologies' stock took a dive in the days following the announcement, and the Wall Street Journal now reports that the company has filed for Chapter 11 bankruptcy protection. Under Chapter 11, companies generally continue to operate as they attempt to reorganize their operations, and GT CEO Tom Gutierrez emphasized that the company wouldn't be shutting down.

"Today's filing does not mean we are going out of business," said Gutierrez. "Rather, it provides us with the opportunity to continue to execute our business plan on a stronger footing, maintain operations of our diversified business, and improve our balance sheet."

Though most reports point to the iPhone deal as the main reason for the bankruptcy filing, Greentech Media points out that the company's solar panel manufacturing operations have also hit a rough patch in recent years. Assuming GT still retains its agreement with Apple to manufacture sapphire for its devices, it could see a rebound once the sapphire-equipped Apple Watch launches in early 2015. Plus, next year's iPhones could still make the jump from glass to sapphire. A look at GT's stock price indicates that it has quite a hole to dig itself out of, though.