Why is it so difficult to extract gold from ocean water?
373269
Gold occurs in sea water at 0.1 to 2 mg/ton (0.1 to 2 ppb by weight) depending on sample location. Compare this to mining from gold ores which is feasible at the level of 1-30 g/ton, depending on depth.\n\nNo wonder no commercially viable mechanism for performing gold extraction from sea water has yet been identified.
62403
Must be another geologist!\n\nLook up the paper in GeoRef.\n\nFind it in the library or get it on interlibrary loan.\n\nLet us know if you find gold or diamonds!
224956
For any kind of electrochemistry to occur, there should be electrolytes present in the fluid to transfer charges.  This is why salt water is more corrosive.
420623
You can't. Alchemy is a myth. Without nuclear reactions, you can't turn lead into gold, or any element into any other element.
707675
Fascinating idea, that, but impractical.\n\nThe oceans are just huge and very deep.  Its not like finding a quart in your swimming pool...\n\nUndersea treasure hunting is an imprecise business at best.\n\nThere are already adventurous souls seeking the probable locations of old treasure ship wrecks and diving for any treasure they might hold.  Generally, IF they find anything, the first have to pay taxes to the government controlling the water they find it in, pay their own expenses (which are sizeable) and finally pay off the investors sponsoring their adventures.\n\nMany people can and Do go broke and never find anything down there.
831148
Sea salt melts it quickly.\n\n\nPeace
566155
it's to do with the magnetic field of the water and or the geology. I did gold exploration for several years and on weekends we'd help the local farmers source underground water. And we used both a magnetometer to chec k for magnetic anonamalies amd then walked exactly the same path with a diving rod, a piece of fence wire and the rod would move at exactly the same places we found magnetic kicks with the magnetometer.
700454
One way to do that for relatively small volumes of water is to force the sea water through a special membrane filter under high pressure. The filter membrane must be constructed so that its holes are large enough to just pass a water molecule, but not large enough to pass metal\nmolecules, salt molecules, algae, etc. The result would be fresh clean water with a lot of brine solution left in the pressurized tank that needs to be dumped.\n\nAnother process which is more poractical for large volumes of fresh water production is electrolisis. In that process, electrical current is passed through the water to break it down into its basic elements such as hydrogen and oxygen (and all the other junk that is left over).\n\nOnce the hydrogen and oxygen are collected and recombined, the result is pure fresh water. Again, the vat or tank holding the original sea water now has a heavy brine solution which must be disposed of somehow. Most any use of sea water to produce fresh water will generate a lot of salty brine by-product that could poison sweet earth in the vicinity if it is merely dumped.
1044077
Actually, we can.\nIf you put lead into an "atom smasher" you can synthesize gold.\nThe problem is that the process costs more than the price of gold.
45495
While Mara gives a good description on the origin of salts in water (all water in general) it doesn't explain why the ocean is salty and streams, lakes etc are not.\n\nBascially the ocean has no outlet. Once water reaches the ocean, it stays there, along with all it's transported salts and minerals. \n\nThe Earth has weather though, and weather is driven in a large part by evaporation of water from the Earth's oceans. \n\nWhen you evaporate the water content, you fractionally reduce the volume of water, which therefore fractionally increases the concentration of salts and minerals. You should also know that some of these salts and minerals are removed from the oceans by precipitation into sediments on the ocean floors. So over the millions of years that the oceans have been around they have grown relatively saltier than the bodies of water that contribute to the oceans.\n\nThis process is exaggerated in trapped bodies of water that recieve a lot of heating. Take the Dead Sea for example - it's an enclosed body of water and since it does not have the vast volume of the world's oceans, the salt concentration process runs much faster. The Dead Sea is currently 6x saltier than the ocean. Salt lakes on any continent are another smaller example again - you'll find them in the USA and Australia to name but two examples.\n\nCommercial Salt production uses the same process, of evaporating water to leave behind salts.
191847
The oceans are in relative equilibrium.  They aren't getting saltier.  There are several salt "sinks" which take the accumulated salt and remove it from the ocean.\n\nThe following is an excerpt from this Web reference on the subject:\n\nb. Sinks (removal processes) of ocean salinity include salt spray which is blown over land; at oceanic ridges magnesium and sulfate ions are incorporated into mineral deposits; calcium, sulfate, and sodium are deposited as biogenous sediments in animal shells and fecal pellets; most importantly, almost all ions can be absorbed to the surface of sinking clay and biological particles.\nhttp://www-ocean.tamu.edu/~duce/chapter07.html\n\nDoing a Yahoo Search for:\nocean salinity salt removal\nhttp://search.yahoo.com/search?p=ocean+salinity+salt+removal&ei=UTF-8&fr=slv1-&x=wrt\n\nyou can find a number of related articles that talk about what happens to the salt.\nhttp://www.palomar.edu/oceanography/salty_ocean.htm\nhttp://www.geo.arizona.edu/geo2xx/geo212_2/Lectures/OC05.SaltGas.pdf#search='ocean%20salinity%20salt%20removal'\nhttp://www.oceansonline.com/salts.htm
967355
try thinking about the energy needed to break the ionic bonds. water can be split, but the energy needed is massive, because the bonds are so stable
684361
A scientist by the name of Gold theorized that the Earth itself produces oil, I can't remember all the details, but the idea is the mechanism for this production is beneath the Earth's mantle, farther than anyone has ever drilled. There is a little evidence to support it, and I believe the Canadian gov't was sponsoring a drilling operation to see if it was true. Gold had a reputation for pushing forth seemingly insane theories that eventually proved true.
1007221
Because of the weight of gold itself, were you to have a large tub of water that had an overflow spout, under which spout there was a container to catch all the water that overflowed, you could fill the tub to the top with water, then having a dish within the tub that was floating free, by placing a gold crown in the floating dish there would overflow out of the tub of water an amount of water equal in weight to that of the crown.  By weighing the water that came out of the tub, a person would know how much gold a crown was formed of.\n\nThe story says that the maker of the crown used a particular amount of gold.  Were he to have used silver as a mixture it would have showed up as there being less water coming from the overflow.\n\nThe story is but an illustration of how Archimedes solved this particular problem.
107751
The easiset way use sea water as a fuel is simply to extract the Uranium from it and feed it into a standard reactor. It's perfectly feasible and possible with the technology we have today.\n\nThe only reason we don't do it is because we have cheaper supplies of Uranium elsewhere.
923875
Salt water is denser than fresh water.
425123
They do indeed contain valuable minerals, some much more valuable than gold.  To set up any kind of large-scale mining operation would cost trillions of dollars using modern technologies, though.  So I don't think it would be worth the cost.  In 100 years, we may very well have off-world mining operations, depending on what technologies develop.