The iPhone 6 does not us sapphire. Apparently Ray Soneira, agrees with me; this is from his DisplayMate website, "
The use of sapphire to make the iPhone screens scratch proof was one of the most talked about rumors over past year as a result of Apple’s $578M investment with GT Advanced Technologies to build a factory in Arizona. The likelihood of sapphire appearing on the iPhone 6 was close to zero because it will probably take at least another year for everything to come together. It is important to note that sapphire has some downsides over and above its much higher cost and manufacturing complexity. The most important issue for display performance is that sapphire has almost double the screen Reflectance of glass (due to principles of optics), so it will be harder to read sapphire screens in high ambient light. That might be one reason why the recently announced Apple Watch Sport edition has a cover glass rather than sapphire like the other models – because it is much more likely to be used unshielded in high ambient light outdoors. Another reason is that while sapphire is very hard it is also brittle and is likely more prone to impact breakage, which is more common in sports situations. So, if given the choice, I personally would choose a cover glass with its better screen visibility and breakage protection. Others may find the scratch protection more important."
There is commonly confusion over display specifications. Many people do not understand the difference between color gamut and color resolution. And it is understandable that a non technical person might not understand the difference between hardness and toughness or the difference between an isotropic glass and an anisotropic transparent crystal. However, a display being fundamentally an optical device, when the discussion turns to a new material in the optical chain, it is amazing that the new material's optical performance could be so widely ignored. In GTAT's promotional literature, they did publish its "index of refraction", for all to see (... that particular page seems to have been removed from the web site. "Oops!.. Sorry about that. The page you requested cannot be found.") However the format of the publishing indicated that "more is better" even though a higher index is exponentially more surface reflection. In "
More is Better, " I detail the problems mobile displays have with surface reflections; how that is the limiting factor on current mobile LCD performance. The amazing hype regarding sapphire leading up to the iPhone 6 announcement just goes to prove that no one actually reads specs.
Update 10/8/14 GTAT filed for chapter 11 on 10/6/14 The stock is now selling below $2 and had been as high as over $20. Its market cap is now just under $240 Million.