I've been farming gold here for a week now at least and there's always up to 4 chests in the instance and every chest has a small chance of containing a valuable item. Most of them contain junk only, however and some of them are even locked! So a rogue or any other class with blacksmithing skeleton keys or engineering seaforium charges is highly recommended. You'll never know what treasures awaits in that locked chest!
So far I've obtained 6 rare recipes that are worth almost 10k gold total. Finding a buyer might not be easy, but there's no reason to undercut when selling rare recipes. Buyers who are looking for them are ready to pay! In addition to those, I've obtained boatloads of greenies that disenchanted into valuable Illusion Dusts and Greater Eternal Essences. Some mobs also drop valuable profession recipes, like Arcanite Reaper and less valuable Robe of the Archmage.
Since there's a limit on how many instances you can visit in a hour (5), it's recommended that while you're in the instance you should also kill everything that crosses your path. All humanoids drop Runecloth and if you have tailoring and enchanting, you can create Runecloth headbands and disenchant them for even greater profit!
There's usually one treasure chest in each of the regions within the zone and they have 2 spawn points usually, so after a few runs you're already familiar with all the treasure chest spawn points.