The world’s biggest island has huge resources of metals known as ‘rare earths,’ used to create compact, super-strong magnets which help power equipment such as wind turbines, electric vehicles, combat aircraft and weapons systems.

The metals are abundant globally, but processing them is difficult and dirty - so much so that the United States, which used to dominate production, surrendered that position to China about 20 years ago.

As Greenland’s ice sheet and glaciers recede, two Australia-based mining companies - one seeking funding in the United States, the other part-owned by a Chinese state-backed firm - are racing for approval to dig into what the U.S. Geological Survey (USGS) calls the world’s biggest undeveloped deposits of rare earth metals.

The contest underscores the polluting side of clean energy, as well as how hard it is for the West to break free of China in production of a vital resource. Rare earth metals have many uses, and last year China produced about 90% of them, according to Toronto-based consultancy Adamas Intelligence. As U.S.-China tensions mount, President Joe Biden’s administration said last month it will review key U.S. supplies, including rare earths, to ensure other countries cannot weaponise them against the United States.

Each Greenland mine would cost about $500 million to develop, the companies say. Both plan to send mined material away for final processing, an activity that is heavily concentrated in China. The only rare earth mine now operating in the United States – Mountain Pass in California – is partly owned by a Chinese state-backed company that currently sends material mined in the U.S. to China for processing — at facilities that are less than optimal for pollution not to mention geopolitical.