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Since you appear to be also looking for DM help, as he didn't figure out how you'd get past his treasure room trap, the DM can easily rule/retcon that 99% of it is actually iron pyrite, aka fools' gold. Based on how the gold was collected, your player with the mage hand didn't see through the illusion in the room that made all of the gold look like the real stuff: the DM intended this to be a trap room, right? The players will find out when they try to spend it that loads of this money "is no good here" as a savvy merchant notices that it's not real gold. Alternately, all of it is copper with the thinnest of gold veneer/plate ... meant to lure the greedy and unwary ...

Since the DM didn't figure out how you'd get past his treasure room trap, the DM can easily rule/retcon that 99% of it is actually iron pyrite aka fools' gold. This is a reasonable retcon, based on how the gold was collected. The player with the mage hand didn't see through the illusion in the room that made all of the gold look like the real stuff: the DM intended this to be a trap room, right? The players will find out that when they try to spend it that "your money is no good here" is a common response. Savvy merchants notice that the coins are not real gold. Alternately, all of it is copper with the thinnest of gold veneer/plate, which was meant to lure the greedy and unwary ...

Coda: for the DM

Since you appear to be also looking for DM help, as he didn't figure out how you'd get past his treasure room trap, the DM can easily rule/retcon that 99% of it is actually iron pyrite, aka fools' gold. Based on how the gold was collected, your player with the mage hand didn't see through the illusion in the room that made all of the gold look like the real stuff: the DM intended this to be a trap room, right? The players will find out when they try to spend it that loads of this money "is no good here" as a savvy merchant notices that it's not real gold. Alternately, all of it is copper with the thinnest of gold veneer/plate ... meant to lure the greedy and unwary ...

1. It's not all about you, it's about your group experience.
2. Your other party members see opportunity where you see worry. Go with their gut feel.
3. You might screw up: so what? Failure and screw ups can lead to hilarious and memorable fun. (We play games to have fun, mostly).
4. If you aren't discrete about your pile of loot, adventure will come to you. Parties of freebooters, pirates, bandits, and other unsavory sorts (like adventurers) may come after your ill gotten gains, filthy lucre, treasure horde, etc. You'll be able, with some planning, to reduce the number of murder-hobos in your game world by simply letting them come to you and taking them out, or by bringing them to justice. (And you'll have the dough to rig/bribe any jury or judge, just to make sure. wicked grin )
5. You may get a visit from Smaug, or your world's equivalent. Dragons love gold. The lore of the book The Hobbit includes the "why" of Smaug coming to Erebor and taking down the dwarves and men of Dale: naked greed. He heard rumor of their wealth and fame, and decided to come and make it his. (Start hiring scouts and archers, eh?)
6. You are being given a chance to explore a question millions of people have: if I won the lottery, what would I do with all of that money?

1. The group can still have fun with this even if your PC is an ascetic. The aggregate experience is the key.
2. You might (as a group) screw up: so what? Failure and screw ups can lead to hilarious and memorable fun. (We play games to have fun, mostly).
3. If you aren't discrete about your pile of loot, adventure will come to you. Parties of freebooters, pirates, bandits, and other unsavory sorts (like adventurers) may come after your ill gotten gains, filthy lucre, treasure horde, etc. You'll be able, with some planning, to reduce the number of murder-hobos in your game world by simply letting them come to you and taking them out, or by bringing them to justice. (And you'll have the dough to rig/bribe any jury or judge, just to make sure. wicked grin )
4. You may get a visit from Smaug, or your world's equivalent. Dragons love gold. The lore of the book The Hobbit includes the "why" of Smaug coming to Erebor and taking down the dwarves and men of Dale: naked greed. He heard rumor of their wealth and fame, and decided to come and make it his. (Start hiring scouts and archers, eh?)
5. You are being given a chance to explore a question millions of people have: if I won the lottery, what would I do with all of that money?

From your comment/amplification, 4 out of 6 are worried that this is too much gold - the DM being one of them, as he didn't foresee the use of a portable hole in that trap room. You don't have to keep it if your collective brainstorming session within the group on what to do with it gets overwhelmed by the order of magnitude involved. Find a cave, dump most of it or all of it down a deep hole, and let fate take care of the rest. Spread rumors of cursed gold if you like.

But if you choose to keep it, or most of it ...