Leveling Mining from 20 to 25

[Savish]

If you have a lot of patience, or a lot of alcohol, just mine iron until you hit 21. I think I got 3-4 full levels from mining iron in my teens and level 20.

Iron is used in frankly obscene amounts to level both Blacksmith and Armorer, since it's needed for both the "iron tier" and the "steel tier." If you don't plan on playing either of those DoH classes, sell it on the market; I'd be very surprised if you couldn't sell it for a pretty penny. I think it goes for around 35-60g per piece on Faerie, though I've never actually bought any.

Silver ore is a nice way of doing 21-26.

Iron ore is also needed to craft cobalt so its basically used all the way up to lvl 50 for both blacksmiths and armorers.