It consists of the melting from the raw compound employing oxyhydrogen flame plus the crystallisation from the melted droplets to type a cylinder. Graded 9 to the Mohs-hardness scale (graded 1-ten), the ensuing sapphire crystals are almost scratch-proof and very challenging, making sure an unhindered vision constantly. TAG Heuer is https://www.watchesworld.com/the-most-coveted-watches-in-the-uk/