|MadSci Network: Earth Sciences|
Gold is present in the ocean in dissolved form at a level of about 6 parts per trillion. That is a minute concentration, but works out at about 6 kilogram per cubic kilometre. No-one has ever found an economical way of recovering this gold.
The answer to your question appears to be "no". The dominant form of dissolved gold in most seawater is in the covalently bonded Au(OH)(H2O)x.
Here is an abstract from the Harvard/NASA ADS Astronomy/Planetary Abstract Service, it is accessible on the web at http://adsabs.harvard.edu
Gold speciation in natural waters: I. Solubility and hydrolysis reactions of gold in aqueous solution Vlassopoulos, Dimitrios & Wood, Scott Geochimica et Cosmochimica Acta, Vol 54, No. 1, pp. 3-12 (1990) Solubility measurements of Au in dilute to concentrated aqueous NaOH solutions at 25°C have been carried out. The data were fitted to the general half reaction Au ( c ) + 2 H 2 O AuO 2 H 4- n 1- n + nH + + e - in order to identify the stoichiometry and stability of the hydrolyzed species formed. The monohydroxide, AuOH(H 2 O) 0 , is found to be the most stable species up to pH ~ 12. The equilibrium constant for the formation of this species (i.e., n = 1) is logK 1 = -22.57 ± 0.44. Consideration of competitive complexation of Au by a number of inorganic ligands which are encountered in natural waters indicates that AuOH(H 2 O) 0 is the most stable inorganic Au species over a wide range of Eh, pH, and ligand activities. The only inorganic ligands which may occur in natural waters at concentrations high enough to stabilize Au(I) include HS - under reducing conditions, S 2 O 3 2- under alkaline oxidizing conditions, Cl - in very acidic, oxidizing brines, and possibly CN - locally, in environments where there is biogenic and/or anthropogenic production of cyanide. Calculated equilibrium pe-pH diagrams for Cl - and S activities typical of both fresh and sea water show that AuOH(H 2 O) 0 is probably the dominant dissolved Au species in these environments, with the exception of anoxic ocean and lake waters.
As an interesting historical aside, extraction of gold from seawater was most famously tried by Fritz Haber. Haber is an interesting character - he was a Nobel laureate in chemistry (for his work on fixing nitrogen from the atmosphere), he is also sometimes referred to as the father of chemical warfare (as the organizer of the first gas attacks in the Great War). In the early 1920's Haber spent a lot of time working on an extraction process to remove gold from seawater, and surveying the oceans for dissolved gold. He hoped that the gold could be used to help pay off Germany's enormous reparations payments from the war. Ultimately, he found that there was nowhere near enough gold in seawater to make extraction economically feasible (by about a factor of 1000).
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