"A new jewelcrafting recipe has been added to transform many green quality gems into a single random blue quality gem. This recipe is available from grandmaster jewelcrafting trainers." --- Yours Truly, Blizzard.
Squorg tipped me off about this yesterday (thx dude!), I didn't actually spot this new entry in the test notes myself. Today I popped in to check it out and I've got the skinny for ya. I bought this for about 2.5 gold from the trainer in Stormspire, I assume you could get it from the others as well. The item is called Brilliant Glass and it is a blue item when crafted. It doesn't say it's a bag, but the tooltip alludes to mysterious goodness inside. Since I had about a bazillion stupid green gems sitting in my bank, I made ten Brilliant Glass objects to see what we might expect.
The mats are 3x of each green gem, so basically 18 green gems to create one blue gem. So far I've not seen any multiple drops from one of the 'glass' baubles. Hrm, they really need to give us a name for this new thing, not sure I want to call it a "brilliant", and a "glass" might be confusing, like I need a drink or something. Perhaps I should make a poll to help us name this new thingy, I'll save that for later tho ;)
The good news is that not only can you use up almost a stack of green gems for each item you make, but there's no cooldown on the combine. So you can craft as many as you want - I know I plowed through as many of my green gems as I could. I ran out of yellow and red though, bummer (what can I say, I've been using them for diamond transmutes!).
Without further ado, here's the data I collected on the gem-combining recipe:
#1 Thingy: Noble Topaz
#2 Thingy: Talasite
#3 Thingy: Dawnstone
#4 Thingy: Dawnstone
#5 Thingy: Dawnstone
#6 Thingy: Talasite
#7 Thingy: Star of Elune
#8 Thingy: Star of Elune
#9 Thingy: Star of Elune
#10 Thingy: Living Ruby
As you can see, for this run I got predominantly lower value gems. I don't know how random it will be in the long run, my sample is obviously pretty small. For me, I don't even care all that much if I get more high value gems or low value gems. I've always hated the idea of vendoring my greenies, and sadly at this point they have next to no value. I'm just happy that I can finally do something constructive with them, I feel no need to be greedy about it =)
I have to say, I'm pretty happy they gave us this option and I've already submitted my feedback on the PTR, thanking them profusely. The gem market has been slowly degrading as more jewelcrafters get in on the act. While I can't blame them for jumping on our bandwagon, it has really killed the green gem market. I'm very pleased to see Blizzard recognizing the problem and giving us an alternative use for our green gems. I know I haven't felt good about adding my green gems to the glut of stuff on the auctions and for the most part they've just been sitting in my bags, taking up space. Praise Elune, now I can do something helpful with them, woot!!