At this point, we can just about assume Apple’s next iPhone will have a sapphire screen. Foxconn has apparently been producing small batches of iPhones with sapphire displays, and Apple CEO Tim Cook has admitted that its plant in Mesa, Arizona will be making sapphire glass. Last week, 9to5Mac uncovered evidence that this plant will begin operating as soon as this month. But what is so special about these sapphire screens? Apparently not even a concrete block can damage sapphire. A video uncovered by 9to5Mac shows just how scratch-proof an iPhone with a sapphire screen would be. In the video, a concrete block is dragged across an iPhone with a sapphire screen protector. Not only does the iPhone come away unscathed,