Apple is really pushing its limits with the upcoming iPhone 6. In a latest 'leaked' parts video, we see 'Sapphire Crystal Display' from the latest iPhone. This is actually a original part right from the manufacturing line and not a dummy.
Sapphire crystal is said to have two very important properties. The first is that it is crystal clear, no pun intended. Apple uses the material in small amounts to protect the camera of the iPhone without fear of the material aversely affecting the sensor. And as the video does show, you can barely discern the presence of the display and there is very little, almost none, distortion in quality or color. Plus, it is also paper thin, which will do wonders for the overall thickness of the iPhone 6 as well as the display's responsiveness to touch.
Here goes the video of the leak