I've found a official statement from two weeks ago that confirmed the GM
What I will say is this: we're out to punish those that exploit WoW, not innocent players. Intent and context play a large part in our investigative process, and those that accidentally purchase ill-gotten items shouldn't fear recrimination.Source: http://eu.battle.net/wow/en/forum/topic/3225593877#11
For a full month, there were no new gems sold in huge quantities over the trade channel. This led me to belief that there was no dupe around and the huge quantities came just from Gold sellers which were out of gold on the specific server.
On friday I've bought 300 Queen's Garnet over trade chat for 600'000 Gold. I thought it was a good deal, since the usual price on my server is 3000g each.
Anyway, a GM deletet the gems out of my inventory and I got a warning not to do such trades again. I was told that I've got an Email with the details, wich however never arrived.
After talking with three different GM's, they all confirmed that this is the new standard procedure for items, that, I quote, "were originated in illigal activities".
Although the gold I invested was made by playing the auction house, thus not originated in illegal activities, I was not refunded it and it is now lost.
If there was or is a dupe method around, I welcome that every single item that originated in it will be deleted. My gold was, however, not duped and should be around somewhere.
My questions now, and I hope a blue can answer these:
Sincerely
Stonewolf