At the same time, Apple and several of its supply chain partners have to make downstream investments to install new equipment to cut, shape, grind, and polish a material second only to diamond in hardness, and to do all that for millions of mobile devices. In addition to money, that all takes time, and trial and error.
There may indeed be yield or other production problems, but neither LEDinside nor AppleInsider present any evidence of that. And the "delay" may be pure myth: all of Apple's sapphire moves so far may be aimed at producing products not for the 2014 iPhone, or other products this year, but for the 2015 models.
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