gold

At 10 parts per quadrillion the oceans would hold 15000 tonnes of gold

The world’s oceans contain gold. Measured concentrations of gold in the Atlantic and Northeast Pacific are 50–150 fmol/L or 10–30 parts per 1,000,000,000,000,000 quadrillion (about 10–30 g/km3). In general, gold concentrations for south Atlantic and central Pacific samples are the same (~50 fmol/L) but less certain. Mediterranean deep waters contain slightly higher concentrations of gold […]