WoW Gold 101 - 101 Ways to Earn Gold In World of Warcraft

Un'Goro Soil, Bloodpetal Sprout and Power Crystals

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Zones (Kalimdor)
Zones (Eastern Kingdom)
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There are some more or less valuable items that you will find all over Un'Goro while adventuring there. In addition to these items having possible demand in your Auction House there are also other ways to take advantage of these items.
Un'Goro Soil

Un'Goro Soil is needed for the repeatable quest "Morrowgrain Research" in Thunderbluff or Darnassus. You need about 40-50 units of soil every time you complete the quest. This builds up your reputation with Thunderbluff/Darnassus which means that there is a constant demand for Un'Goro Soil and you should be able to sell it in the AH.

Bloodpetal Sprout

Bloodpetal Sprouts can be turned in for the repeatable quest "Dadanga is Hungry!". The quest gives you some experience and the Small Brown-wrapped Package. This package usually contains just food and some points. If you are lucky enough to hit the jackpot you might get Recipe: Elixir of Brute Force which sells for hundreds of gold.

Power Crystals

Power Crystals can be used for Blacksmithing and can also be used to create 4 kinds of buffing crystals after you've got the Crystal Pylon User's Manual. You can get the manual by doing quests for the guy (J.D. Collie) in the cave in Marshal's Refuge. The 4 kinds of buffing crystals are:

Crystal Restore = Yellow + Green + Northern Pylon

Crystal Force = Green + Blue + Eastern Pylon

Crystal Charge = Yellow + Red + Northern Pylon

Crystal Ward = Green + Red + Western Pylon