It consists of the melting from the raw material applying oxyhydrogen flame along with the crystallisation in the melted droplets to kind a cylinder. Graded nine about the Mohs-hardness scale (graded 1-ten), the ensuing sapphire crystals are nearly scratch-proof and very really hard, ensuring an unhindered eyesight all the time. https://www.watchesworld.com/the-most-coveted-watches-in-the-uk/