If gold suddenly becomes worth 10,000 an OZ after being worth only 1300~.... doesn't the economy completely and utterly explode?
No, it means that gold's value becomes $10,000 USD/oz. It also means that people will have a reason to actually mine it, as it is a scarce and valuable resource used in many of the items used today, even the one you are using currently.
The economy will not explode because of one commodity becomes super rich and/or super poor. It may effect it if a lot of that commodity is tied to the economy (like oil) but it will never do more than temporarily disrupt it (everything corrects itself to adjust to the new price point of the commodity).
Take oil for example. When oil went up to $157/barrel, gas prices, among other things, were extremely expensive. Some states, like California, experienced gas prices as high as $6/gallon.
While it did disrupt the economy (global in this scale) due to almost double, and in some cases, triple the price to move products, what happened was that the prices of products increased to compensate. In a normal economy (what we experienced in 2009-2016 was anything other than normal, but that's a completely different argument), labor would have risen to match the price increase due to higher demand for wages to cover such increases. However, that did not occur due to other higher increases to the cost of labor (mainly due to Obamacare, but job-stiffing tax increases plus extreme over-regulation also played a contributing factor). Therefor, due to higher costs of labor, the oil prices had no choice but to go down due to lack of employment (added technology, such as fracking, also played a contributing factor to this too). The over-regulation/tax increases/bad laws enacted did more damage to the economy than any "price shock" as you are asking for would ever do.
If I have 100 oz of gold, I instantly become a millionaire?
Only if you sell it then. If you hold it and it goes down, then no. Even if you sell it, you have to pay capital gains tax on top of that, and lose an automatic 23.8% of the value of gold. More like 23.6% after you take away other deductions on your tax return.
You would have to sell close to 140 ozs to actually gain a million dollars after taxes.
And that's assuming that you are
not in the business to buy and/or sell gold. IF you are, then that's not capital gains, but ordinary income, and are subject to 43.4% taxes.
And all this, this is just
federal taxes. Additional taxes depends on the state. California, who has the highest state individual taxes in the nation, would tack on an additional 10.3% tax on top of all that. Regardless of the classification (California doesn't recognize capital gains tax, as they consider it a cause for cancer only in the state of California).
I don't understand how Trump can just decide that gold is now worth $8000 more arbitrarily.... without causing absolute chaos.
He doesn't. He has
very little effect on prices of commodities, and he can
never set a price on one.
Where did you get that sort of information?