Apple just bought upfront $578m of sapphire glass. In addition , Apple is building a manufacturing plant in Arizona that will be used by GT Advanced Technologies to make sapphire crystals for use in its products. Apple currently uses sapphire in its home buttons and camera lens covers, but now it seems Apple with GT are expanding its interests in the hard crystalline substance over the next several years.

So what will Apple do with all this sapphire. Well the iPhone retina screen will be upgraded in 2014 and sapphire could be used going forward. The iWatch could do with a scratch resistant glass. And if an Apple TV really does materialise maybe this. And of course the next wave of iPads.