For 10 points, name this mineral of Mohs hardness nine, the red form of corundum.
This precious stone typically displays needle-like intrusions of rutile, and like common mimicks of diamond, this mineral is produced in large scales by the Verneuil process. Synthetic rods of this precious stone are used as a gain medium in some lasers. Its characteristic color comes from chromium, and its most valuable shade is called pidgeon's blood. For 10 points, name this mineral of Mohs hardness nine, the red form of corundum.
This precious stone typically displays needle-like intrusions of rutile, and like common mimicks of diamond, this mineral is produced in large scales by the Verneuil process.
{ruby} [accept {corundum} before mentioned]