It is an anti-wear material, along with tungsten-titanium alloys and high-tech ceramics. While these materials are resistant to wear, they cannot withstand strong impacts and can be scratched by substances of equal or greater hardness, such as whetstones, sandpaper, nail polish, granite surfaces, concrete walls and floors, etc.
The sapphire is a natural sapphire that is used in the manufacture of watch mirrors.
Sapphire is the common name for corundum gemstones of all colors except red ruby, whose main component is aluminum oxide. Sapphire glass refers to synthetic sapphire, which can be easily and inexpensively produced in a laboratory as gem-quality sapphire with the same chemical composition and physical properties as natural sapphire.