Sapphires are recognized as being one of the hardest minerals, coming in at a 9 out of 10 on Mohs Scale of Mineral Hardness. This scale is determined by the ability of harder materials to scratch softer materials. It is for this reason that many luxury watch manufacturers use sapphires for the crystal (the protective “glass” over the dial) of the watch. However, these sapphires are synthetic - created through a process of fusion and crystallization of alumina, then polished and treated with an anti-glare coat on both sides of the crystal. This process creates a “crystal clear” crystal that is extremely scratch resistant and functional. All of the brands that Schwanke-Kasten Jewelers carries, such as Breitling and TAG Heuer, use synthetic sapphire crystals for their watches. Stop by our Whitefish Bay location to browse our complete collection of fine Swiss timepieces, maybe you’ll consider one of these as an alternative September birthstone option.