Apple is repurposing this First Solar facility to create sapphire glass:

Apple will build a new 700-employee manufacturing facility in Mesa, Arizona, to make sapphire glass, according to releases from the State of Arizona and GT Advanced, a New Hampshire-based materials manufacturing company. Apple purchased the vacant manufacturing building from First Solar, and has contracted with GT Advanced to “own and operate furnaces and related equipment” at the facility.

Question is, how will Apple use sapphire glass. An alternative to Corning’s Gorilla Glass 3 for smart-phones? As a crystal for a smart-watch? Time will tell.