It will involve the melting in the raw material making use of oxyhydrogen flame along with the crystallisation from the melted droplets to variety a cylinder. Graded 9 to the Mohs-hardness scale (graded one-ten), the resulting sapphire crystals are nearly scratch-evidence and very tough, ensuring an unhindered vision constantly. Linkedin https://www.watchesworld.com/the-most-coveted-watches-in-the-uk/