Rune Pickaxe

If you fancy a giggle, watch an amateur try to mine runite. Grab a chair, pull yourself a dwarven stout, and watch the carnage.

Runite, you see, actively repels a pickaxe. It twinkles with magic, and that magic - perhaps through some kind of geological evolutionary step - resists any attempt to mine it. Artlessly swing a pickaxe at a clump of runite and the pickaxe will bounce backwards, boomeranging towards the miner's head. There's a reason why field medics are posted at dwarven mines.

The secret is that runite is soft. Not as soft as clay or gold, perhaps, but softer than most metals. You don't need to swing your pickaxe hard or fast. All that is needed is some finesse and patience. Better still, a runite pickaxe will disrupt the magical fields around the ore, pushing the ore out of the rock.