As terrestrial mines begin to run dry, mining companies are turning to source a new source for precious gems and metals: the ocean.

Since the 1960s, diamond company De Beers, which has a 50:50 relationship with the Namibiangovernment known as Namdeb, has been , according to National Geographic. But with diamonds expected to run out on land in as little as 15 years, the company is turning more and more to the seas.

To protect its interests, De Beers is in preparation for future expansion into the ocean, the Telegraph reports. In fact, marine gems are currently getting the highest prices from all of the company's seven mines, and it is estimated that 95 percent of its diamonds will soon come from the bottom of the ocean, reports the newspaper.

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“Marine diamonds are our future,” Paulus Shituna, acting CEO of Namdeb’s trading arm told the Telegraph. “Ten years ago it was 30 percent marine and 70 percent land, but now it’s flipped on its head.”

Mining Other Precious Gems and Metals

Diamonds are not the only precious commodities being considered for deep sea mining.

Gold, copper, zinc, silver — you name it, humans are getting close to , reports Market Watch.

As time runs out, the next big gold rush may very well take place at the bottom of the ocean, National Geographic reports.

According to scientists, there is enough gold on the seafloor to give every person alive nine pounds, worth about $21,000 per person. The estimated total amount of gold to be found at the bottom of the ocean is about $150 trillion.

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Until now, deep sea mining was merely a pipe dream for companies hungry to find the next source of precious gems and metals as mines on land dry up.

One project in the works that could set the standard and begin a boom for deep sea mining is the. Owned by the Canadian companyNautilus Minerals, the project is expected to be ready to begin harvesting gold, copper and zinc from a depth of 3,400 feet 20 miles off the coast of Papua New Guinea by 2018, according to an environmental impact study conducted by the company.

Opposition by Environmental Groups

Environmental groups opposed to Solwara 1 and other deep sea mining initiatives are warning that mining at the bottom of the ocean could be highly detrimental to the ocean's fragile ecosystemand have far-reaching impacts on marine wildlife, local economies that depend on the sea, as well as food sources for humans.

Diamond mining ship at Luderitz, Namibia.

(Thinkstock)

At a Glance

With terrestrial mines running dry of precious gems and metals, companies are turning to the sea.Environmentalists warn of serious and far-reaching impacts of mining at the bottom of the ocean.

According to

, an independent environmental impact study commissioned by the company, concluded that there would be little harm caused by deep sea mining and has "the potential to significantly reduce social and environmental impacts commonly associated with large surface terrestrial copper mines."

Nautilus CEO Mike Johnston said, "Seafloor mining has the potential to not only provide economic benefits within the communities nearest to the operations." It also has "the potential to change the physical nature of the mining industry for the better.

"We believe that the proposed Solwara 1 project will launch a new frontier in the blue economy and resource sector. As the first publicly-listed company in the world to commercially explore seafloor mining opportunities, Nautilus is committed to leading the way and setting a high bar for developing an environmentally and socially responsible approach for the industry. Commissioning this report is part of our ongoing process to review, estimate and evaluate project impacts through objective third-party experts," Johnston said.

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Payal Sampat of Earthworks mining program said in a critique of the project published by the that “comparing the impacts of Solwara 1 to selectively chosen land-based mines is like comparing apples to oranges,"reports Mining News Weekly.

"Nautilus commissioned a study that purports to make a case for seabed mining but which neglects to value marine ecosystem services, or consider the likely impacts on seawater quality, marine ecosystems, or communities [that] depend on healthy oceans,” he added.

Deep Sea Mining Campaign coordinator and report co-authorDr. Helen Rosenbaum said "the risk of unexpected costs and losses [owing] to unpredicted environmental and social impacts is high and could leave coastal and island communities carrying the brunt of the burden into the long term.”

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