Germany is pinning its economic hopes on future-oriented industries such as solar panel manufacturing. But high-tech companies are facing shortages of essential metals as China, which dominates the world market in so-called rare earths, begins stockpiling the highly sought-after resources.

A massive gray mountain rises from the vast plains of Inner Mongolia. The artificial hill is the pride of the Chinese and the envy of the world - at least the world of commodities traders.

Workers at the Bayan Obo mine refer to the mound as "Treasure Mountain." Up to 6,000 people work at Bayan Obo, China's largest mine, which is completely inaccessible to the outside world. The Chinese authorities are intent on ensuring that no outsiders should gain access to the crater-like landscape, and for those who do somehow manage the feat, it is akin to arriving on another planet.

There is not a speck of green on the site, only the monochromatic monotony of earth and debris. Massive dump trucks rattle around the desolate landscape, looking from a distance like giant bugs. They crawl down into the open-pit mine, which is more than 1,000 meters (3,280 feet) deep, and later crawl back up to the surface, heavily loaded with iron. It is because of these trucks that the treasure mountain continues to grow from one day to the next.

A sign on the edge of the heap lists the 71 substances it contains: iron, of course, as well as 17 metals with hard-to-pronounce names like yttrium, dysprosium and neodymium, the so-called rare earth metals. These metals, used to manufacture high-tech products like lasers and solar panels, are coveted and expensive.

Nowhere on earth are larger amounts produced than at Bayan Obo. About 40 percent of world production comes from these mines, and the People's Republic satisfies a total of 97 percent of global demand. In other words, China controls the world market.