The toughest screen protector on the planet Sapphire is a very hard gemstone right next to diamond (10), with a rate of 9 on the Mohs Scale of Mineral Hardness. According to the scale, Talc (1) is the softest: it can be scratched by all other materials. glass (6) is harder: it can scratch talc but not quartz (7), which is even harder. The hardness of a mineral is mainly controlled by the strength of the bonding between the atoms and partly by the size of the atoms. It is a measure of the resistance of the mineral to scratching. Shellrus Sapphire is cut from pure lab made sapphire ingot with a thickness of 0.23 mm. Experiments have shown that Sapphire can handle significantly more scratches and forces than any glass screen protector. Our screen protectors are perfect for outdoor activities that are dusty. Attention: Minerals are more brittle when their hardness go up, thus it's possible for sapphire to crack like glass when dropped. As drops involve too many unmeasurable factors, we will not provide warranty for damages caused by normal usage. A sapphire screen is more awesome than you think​ Sapphire X is certified by GIA, buy now to enjoy the smooth and luxurious swipes on your fingertip. Cleaner than glass Glass is rough under the microscope no matter how smooth it looks, and bacteria will grow over time. Sapphire (3.98 g/cm3) is much denser than gorilla glass (2.42 g/cm3). Our unique chemical polish process will also ensure a smoother surface. Light transmittance is as high as 99% Sapphire has a 99% transmittance under visible light (450-650nm). World-leading technology A sapphire screen protector takes a total of 30 days to produce, we are using the most advanced equipment and tec.