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Elementium Farming
Elementium Depths
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A great spot for farming elementium is, funnily enough, in the Elementium Depths in Twilight Highlands.
This will be quite useful for when the Uldum nodes get hotfixed.
There are however quite a few mobs in here, but most of them are easily navigated around and shouldn't cause you too much trouble.
I've often had 2-3 rich veins within 100 yards of each other!
Maps - World of Warcraft
Hope you enjoy it :]