Depends on what you mean by “oxidize”. Neither silver nor copper will readily combine with oxygen, and are sometimes also considered “noble metals” for that reason. They will, however, combine chemically with various other things in the environment, in a process which a chemist would describe as “oxidation”, which does not neccessarily involve oxygen itself. But there are very few things which will oxidize gold (in either sense), and none of them are commonly found in the environment.
ParentalAdvisory, I think one of the types of spectrograph on one of the Mars missions can, indeed, identify any element at all, but only if it’s within a meter or two of the surface. Any gold on Earth that close to the surface would long since have been found by other means. Or, if you’re thinking of Fort Knox-style hoards, it’d probably be easier to find those by differential gravitometry than by spectroscopy: Gold is much more dense than most other substances (nearly twice as dense as lead, and close to osmium, the densest element), and so a large concentration of gold would produce a measurable change in the gravitational field.
even if you could fill a spacecraft up with rocks, send it into orbit and then have it return magically filled with diamonds, the cost of the mission would still outweigh the value of the diamonds. Getting stuff into space is very, very expensive.
Besides,we all know that probes that return from other planets tend to carry viruses that cause the recently deceased to return to life and begin eating the living.
My dad’s a mining engineer, and he’s personally examined half a dozen sites on Earth with very rich gold deposits that won’t be turned into mines until the price of gold gets high enough to warrant development. (Say, US$700-800). There’s one site in Costa Rica…
So…when the price of gold is several million dollars an ounce, then maybe we can start thinking about how likely it will be that NASA is secretly mining it on other planets…until then, this dog is done.
There’s no reason to mind any metals on any planet. Living heavy materials from one gravity well in order to move them to another is and will remain grossly cost-prohibitive baring some kind of beanstalk technology. Fortunately, your average nickel-iron bearing asteroid probably has a wealth of precious metals…which, unless you form a cartel and be parsimounous about selling it off, will flood the market and make it all worthless, or at least massively reduced in price. At any rate, the only transportation expense you’ll have is moving it to Earth, and allowing gravity to do the work of bringing it down.
There’s not much reason to think any of them will be gold mines either. Earth is the densest of the rocky planets (5.51 g/cm^3), surpassing even Mercury (5.43 g/cm^3).
Y’all are missing the point–sure, it’s not economical to mine for gold on other planets. But if the taxpayer picks up the tab and the scientists can covertly sneak back some gold for themselves, it’s pure profit!
