Resources in one cubic mile of sea water
lifeisstillgood: cperciva, thank you for clarifying what I should have put in there in the first place.Anyway, this seems a good overview and is not wildly out with the other literature afaik.http://books.google.co.uk/books?id=LbTDLa_2opsC&pg=PA26&...so, 130m tons of salt is supported, 6m tons of magnesium, but 1 ton of silver and 0.02 tons of gold, and commercial extraction seems limited to salt (obviously) magnesium and bromine.  I suspect someone quoted the "boring" elements accurately and then upvoted the "fun" elements for you.