My exp with a 70 mage for farming the best ways are to either a) aoe farm for netherweave on lower mobs (as was said) b) farm the eels just outside shat for motes of water - primal waters, only real way for you to farm primal water if your frost specced btw. c) farm primal fires in shadowmoon from the fire elementals (if your not fire specced) or farm primal manas from the Mana Seekers and Mage hunters in Netherstorm, just south from Cosmowrench in the abandoned town there, they're worth less than primal fire, air, water, but drop more and the mobs are easier, so works out even more cash than the other primals i reckon so far.
Anyways gl with the farming

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