|Image Credit: bytelove.com|
This little trick is that I wait for the Jewelcrafting daily to come up that requires gems cut, once I see that the daily requires X gem I go to the AH and list them. Why? Why wait for the daily to require a gem? Because the demand for X gem will be insane. Sure you can sell Nightstones, Zephrydites, & Jaspars when it's not the daily but I find when the daily does require one of the three gems, prices go up, and they stay up for most of the day.
I've sold as many as 150 Nightstones in one day at 45-60g/per gem. One of the great things is that the quest requires three gems instead of one or two, thus people buy them in packs of three. I've also barked in trade some offering to sell gems 5% cheaper than the current AH prices and you'd be surprised at the amount of people who will take up this deal.
Another thing I found is that I can leave up my gems for 24 hours and they will all sell, even if I get undercut minutes or hours later, my gems still sell. Why? Because there is such a high demand for these gems and no one has enough supply to post, so my gems will be eventually be the lowest priced gem at the Auction House.