Ill Walk you through.
The first thing you do is
http://img87.imageshack.us/img87/8948/1stepfv9.jpg
Enter The Marketplace and go to Wejjin Bazaar
The 2nd thing you do is
http://img70.imageshack.us/img70/377/4stepuj8.jpg
You take a left and head in this direction, DON'T USE KEY AT THAT CHEST
The 3rd thing you do is
http://img125.imageshack.us/img125/2327/7stepay4.jpg
Weither the chest has spawned or not, enter The Undercity and exit again UNTIL IT RESPAWNED
the 4th thing you do is
Go to the chest when it has respawned
http://img125.imageshack.us/img125/7627/11stepzo7.jpg
See? it will always be gold, sadly, I don't have the time to post all pictures
The 5th thing you do is
http://img50.imageshack.us/img50/6011/14stepsx4.jpg
Repeat over and over, until you get happy ith how many gold items you have
http://img50.imageshack.us/img50/6011/14stepsx4.jpg
NEVER GO TO THIS CHEST AT THE LEFT SIDE OF THE AREA
http://img74.imageshack.us/img74/766/12stepur2.jpg
I've heard that it took you guys like 40 times, well, it takes me from 1-7 times for the right chest, but sometimes it purple, and I was like WTF, the I figured out the spawning. I was getting dumb luck before, I'm not sure this is only for the weekend event. Keep in mind that the chart has about 25% Bigger circles than it should be (hard to draw circles that arn't at right size)
http://img134.imageshack.us/img134/8844/mapchartin0.jpg
Hope this helps.
Thats about it for this Farming guide, I'm not sure that the pictures will show or not, so don't leave reply's when there not there. OK, I got the pictures up. Sadly, Imageshack is unbelieveable slow, and the pictures are only showing in URL showing.