The glass-like covering over the face of your watch is called a “crystal.” There is usually another crystal in the case-back if you have a mechanical automatic movement in your watch. For many years there were two basic varieties of crystals used in the watch industry: mineral and sapphire. While they came in different grades, sapphire was always considered to be the best because of its hardness.

Sapphire crystals for watches are created in a laboratory environment and they have the same chemical properties as corundum which has a hardness of “9” on the Moh’s scale of hardness. (The only substance with hardness greater than sapphire is diamond which has a hardness of 10 on the Moh’s scale.) Because of their hardness, sapphire crystals contain the most “scratch resistancy” available in watches. However, sapphire crystals are prone to breakage due to the brittle nature brought about by its ungiving attributes.

Approximately four years ago, a new substance appeared in crystals in the watch industry, Krysterna™. Krysterna™ was born from the eyewear industry and comes from the same material used in high-end eyeglasses. Stührling Original was one of a handful of watch manufacturers that was involved in the early stages of testing and development of this new material in watch crystals. Krysterna™ actually has more strength over a spread surface area than sapphire! As a result, this still relatively new synthetic material is more “shatter-resistant” than sapphire!