So far
Best place to Farm Volatile Fire is in Humboldt Conflagration killing Unbound Emberfiends just above Thundermar in the Twilight Highlands
Best place to Farm Volatile Water is in the Verrall Delta killing the Muddied Water Elementals between Firebeards Patrol Dragonmaw Port
Best place to Farm Embersilk Cloth is on the Twilight Shore between Highbank and Dragonmaw Port – killing Axebite Marines ( for Alliance – assuming for horde it would be Highbank Marines.
I like that they are all near each other – the fires and waters are still selling for a bit on the AH, and they have been good for crafting
I found that the respawn rates for the Fire and Water are ok as you just move around the zones.
The Marines for the cloth respawn constantly
There might be better places, but these are the areas I found to be the most convenient, with a decent drop rate, and because the initial questing frenzy seems to have calmed down the zones are not populated often – so mobs are free and clear.
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Pugnacious Priest's Warcraft Blog 
If you fish, there are “Pools of Fire” at Cannon’s Inferno in Twilight Highland that have a pretty quick respawn, and can be fished without aggroing nearby mobs (at L85, at least). I was able to get 60 or 80 over a short period of time while finishing up quests there.
Good thought on the Embersilk cloth, was wondering where to farm it. Tailoring takes so much.
Neat tip, if you’re going to farm your own Embersilk cloth, take the time to use a Potion of Treasure Finding. It’ll up the drop rates on Embersilk cloth and give you a little extra volatiles.
I have been farming the marines for cloth lately, and it has been great. Not only do they respawn constantly, but the friendly ones will tank them for you(saving you on downtime), you are a short flight from the Org portal for training as you pass milestone points or to empty your bags at exalted prices, to craft you just need to head above the beach to where there are no enemies, and if you capture the beach head you get bonus sp/ap.
they must of changed drop rates cause was here for cloth and got 6 in a half hour
Just spent about 2 hours here to farm volatile fires. I am also a miner so I picked up a few nodes as I killed these guys.
Honestly this is a great spot to farm for non miners. I found a ton of greens I was able to DE as well. The only downside to this spot is that the vendor trash greys are not worth much but oh well.
Thanks for the info on this spot, I didn’t even know fire elementals were up here.
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