Best bet is for just gold is to head to the other side of the dungeon and kill the wyrms.
They die just as easily as the ogre lords, but give barbed leather, which sells for a lot of gold. Be sure to bring a butcher's war cleaver and a bag of sending.
The spawn rate isn't phenomenal, but you'll make a lot of gold, hides, gems and scales quickly.
The best way to make gold with a mage is by doing champ spawns, but those are best done in teams. Then you get a lot of gold, possible set items at the end as well as possible SoTs (the pink scrolls that can give skill gains). The market on SoTs isn't going down any time soon. And if you're brave (or stupid) and can get away with spawning in Felucca, then you can also get power scrolls.
The downsides of spawning is that it's a higher risk proposition than normal grinding and if you don't do it with a team, it's rather slow.
The only thing my mage does lately is Ilshenar-spawning or Peerless, both in groups of 3-4 people (minimum).