What mining really needed was a few more types of metal at the endgame,
so those have been added. In the expansion, there will be two types of
high-end base metals (Fel Iron and Adamantite) and two rare metals
(Eternium and Khorium). Also, just like herbalists, miners will find
that some of the strange inhabitants of Outland yield up rare materials
for the forge-fires when they're slain. Miners will be able to "skin"
these monsters to gain the materials used by engineers and blacksmiths
to make their unique items.