Rumours of an iPhone 6 with a sapphire crystal display have been making the rounds for quite some time now. If the latest iPhone 6 display video is any indication, Apple's next iPhone could have the toughest screen yet. But it's probably not pure sapphire.
YouTube tech guru Marques Brownlee has taken it upon himself to rub different grades of sandpaper over a reportedly genuine iPhone 6 screen. He did the same to an iPhone 5s (rather him than us), and the results show that the iPhone 6's screen is noticably more durable than the iPhone 5s, which suffers. Heavily.
The fact that the sandpaper still leaves a mark on the iPhone 6's screen suggests that the iPhone 6 (or at least, the 4.7in variant) will not have a pure sapphire screen.
Pure sapphire glass can only be scratched by diamond, and this is proven by the iPhone 5s' pure sapphire Touch ID Home Button, which is unscathed in the sandpaper torture test.
It's likely therefore that the iPhone 6's display is either a newer, improved version of Gorilla Glass, or a hybrid sapphire-coated screen, which cropped up in an Apple patent last year.
Either way, it looks like the iPhone 6 should survive your jeans with ease. Just as long as you're not walking around with scraps of sandpaper in your pockets.