Rune is one of the the best things you can dig up out of the ground, next to maybe lost knowledge of some unknown civilization. Place one of these in a smelter with 8 coal ore, and it produces a rune bar. For a set of full rune armor, tools, and your choice of sword or scimitar will cost 264 coal ore, in addition to 33 rune ores.
Stats[]
Harvest level: 6
Uses: 4500 (Scimitar: 5500)
Efficiency: 20.0
Damage: 7 (Sword: 11, Scimitar: 9)