Chromium and ferric oxides are used in a flame fusion process to create one form of this this mineral in a technique named after Verneuil.
Chromium and ferric oxides are used in a flame fusion process to create one form of this this mineral in a technique named after Verneuil. Rutile silk cause a notable asterism in one form of it, and Gaudin's synthetic creation of it was the first for any gemstone. An orange form of this substance is known as padparadscha, and it is comprised of (*) aluminum oxide. This gemstone can get a red color due to chromium impurities, and its forms include emery, sapphire, and ruby. For ten points, identify this mineral which has a hardness of 9 on the Mohs scale.
Chromium and ferric oxides are used in a flame fusion process to create one form of this this mineral in a technique named after Verneuil.
corundum (accept aluminum oxide or Al2O3 before mention; accept ruby until “padparadscha”) &lt;EnC&gt;