By Anupum Pant
We’ve been mining gold for about 6000 years now. It isn’t totally clear how much has been mined yet. Still, there are a few reliable estimates which say that about 150,000 to 170,000 tonnes of gold has been mined till date. The 170,000 tonnes figure is the most reliable estimate, which would mean that the amount of gold ever mined can fit in a not-so-massive cube with each side measuring 21 meters. However, some estimates take the figure up to 2.5 million tonnes.
That said, how much more is yet to be mined then? A good estimate is that about 52000 tonnes of gold is still out there that can be realistically mined. But is that all?
No. 52000 tonnes of left over gold might be economically viable, but there are places here on earth which hold massive amounts of gold. It is in the oceans. No, not in treasure chests of sunken pirate ships.
In the ocean waters there’s about 20 million tonnes of gold waiting to get harvested. Although there isn’t a good method by which this can be extracted, it sure is a massive amount of gold. The gold is so spread out in the waters that you’d have to process billions of litres of water to find one gram of gold. The concentration is in the orders of parts per trillion. No one knows how to extract that.
Now, that’s the gold dissolved in water. There’s also gold trapped in the sea bed, just like we have it here on land, in rocks. Even that is 4-5 kilometres under the sea. And it’s trapped in rock there. So, no one has a good way to extract that too.
via [Oceanservice]