When Mists of Pandaria expansion was released Spirits of Harmony was the original crafting material necessary to make high end armor and weapons. As the buying wow gold expansion continued different spirits were introduced (Blood Spirit, Haunting Spirit etc.). In this discussion we're going to talk about the Spirits of Harmony.
If you have done any dailies in Isle of Thunder you should have a decent amount of Spirits sitting in your inventory. While finishing my dailies I usually end up with between one and three a day. Combine this with having my farm in Halfhill producing 16 motes of Motes of Harmony I generally can end up with 5 or more per day to work with. As with any crafting mat, the higher the mob killed generally the better chance of having one of the Motes of Harmony drop for you. So at level 87 mob will probably not have as plentiful a loot table when it comes to Motes of Harmony as does the level 90-92 mobs sitting in Isle of Thunder or Isle of Giants. Now I'm sure someone will point out that this is faulty calculations because they know if they sit farming in one place for long enough they will stock up on motes. Your milage always may vary depending on what farming technique you have.
The easiest way to determine the value of your Sprit currently is based on your professions. Blacksmithing, Tailoring and Leatherworking has the most outlets to determine value. Here's an example.
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