Gems for the pocket
Selling gems is certainly not for everyone. The auction house deposit for gems is a painful 60 silver and 50 copper for a 12 hour deposit. Imagine posting a gem for 48 hour duration and expiring has already cost you 2 gold and 70 silver. In my server, rare cut gems (those recipes that are bought/world drop) can even go as low as 7 gold. If you do the math, even if you sell a 7 gold gem, depositing it for around 2 gold only profits you a puny 5 gold. Is selling gems still worth it?
What gems to sell?
It’s quite hard to sell gems when you don’t know what raiders need. If you have only one lvl 80 character that raids, most likely you only know what your class needs. Go around Dalaran, look at famous guilds in your server and see what they’re wearing. Even easier, ask your guildmates/friends! Do a little research in Wowhead.
How long to post gems?
I’m not really a fan of posting gems for 24-48 hours. It’s up to you and your server though. I post my gems for 12 hours only for a minimum deposit of 60+ silver. If it’s not sold within 12 hours, most likely someone has already undercut you. I’d rather let it expire that sit there for 48 hours paying rent for my gem to sit like a duck.
When to sell gems?
I really mean that selling gems is not for everyone because if you want to sell your gem for as high as 50g, you really have to know your server’s activities. For instance, I have noticed that a few hours before a raid, the AH is full of cheap gems posted by this gem-hog (insert samurai name). When raids are ending, his gems get sweeped by the overly-excited raiders with new gear. By the time his gems are gone, there are none left in the AH and that’s where I step in. His enduring forest emeralds (just for one example), which he posted 7g are all gone so I post mine at around 35-38g. I control the monopoly so I set the price. Raiders who started late or just ending because of wipefest still need gems for their new gear. Hence, gem sold for 35-38g for enduring forest emerald. Evil laugh.

