When we look at it, we see a lot of disadvantages of Sapphire versus Gorilla Glass. It’s about 10 times more expensive. It’s about 1.6 times heavier. It’s environmentally unfriendly. It takes about 100 times more energy to generate a Sapphire crystal than it does glass. It transmits less light which… means either dimmer devices or shorter battery life. It continues to break. I think while it’s a scratch resistant product it still breaks and our testing says that Gorilla Glass (can take) about 2.5 times more pressure that it can take…Sapphire on. So when we look at it, we think from an overall industry and trend that is not attractive in consumer electronics.
This could just be Corning dissing Sapphire glass because Apple has decided to use it instead of Cornings own glass.
Personally I believe Apple won't use Sapphire glass for the iPhone, it will be for their smartwatch - the iWatch.