The phrase "sapphire screen" refers to a type of screen, commonly used in electronic devices like smartphones, that is made from a hard and durable material called sapphire. Full definition
Let me know your thoughts on the possibility of iPhone 6 with a 4.7 - inch 5.5 - inch sapphire screen in the comments below. (iphonehacks.com)
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. (displaymate.com)
In addition to the possible sapphire screen, the iPhone 6 is expected to have an aluminum back panel. (ibtimes.com)