I was curious as to why corundum ore appears in Skyrim. Also why iron ore + corundum ore = steel ingot? According to the wiki and other sources corundum is a crystalline mineral used as an abrasive. It isn't even a metal ore (aside from trace elements).

Steel production normally involved the use of iron ore processed for impurities and smelted with pig iron using charcoal or coke. If anything a steel ingot should be made using iron ore and the (currently near-useless) charcoal item in the game.

I'm not complaining, since it doesn't really matter. I was just curious as to why this is, and if corundum has appeared in any other Elder Scrolls game?