Editor's Note: The following is an excerpt from Tom Zoellner's book Uranium.

One of the most potentially dangerous places in the world is called Shinkolobwe, the name of a now-destroyed village in central Africa which took its name from a thorny fruit resembling an apple. After boiling, the outside of the fruit cools quickly but the inside is like a sponge. It retains hot water for a long time. Squeezing it results in a burn.

The word is also local slang for a man who is easygoing on the surface but becomes angry when provoked.

A local story around Shinkolobwe says that a deep pit near the remnants of the village is haunted by a spirit named “Madame Kipese,” who lives inside the pit. The Madame had been a lively and forceful woman when she was alive, but had grown evil after her death and burial. White men had come here many years ago to dig the hole and had become friendly with her. They may have even had sex with her.

Madame Kipese needs to consume human souls to keep herself strong. She emerges from time to time to kill someone. Unexplained deaths in the area are sometimes attributed to Madame Kipese.

“I would not go there myself,” an officer from the federal police told me. He was on the protection staff of Joseph Kabila, the president of the Democratic Republic of the Congo.

“It’s a very dangerous place,” he went on. “Cell phones burn out when you take them there. Television sets won’t work, even if there were a place to plug them in. Be sure you don’t wear a T-shirt. You must wear a long-sleeve shirt to protect yourself from the dust. All the men who work there are supposed to wear long-sleeve shirts. Try not to breathe the dust. Whatever you do, don’t put any of that stuff in your pocket.

“Are you sure you want to go?”

I told him I was sure.

“You have to cross through at least four roadblocks before you get there,” he said. “Each one is more serious. That place is very heavily guarded. It is considered a strategic site. They want to make sure you are not a saboteur. The last line of defense is a squad of United Nations soldiers. I won’t be able to help you with them.”

I wound up paying him $80 for what he described as a special police authorization.

The next day, I received a photocopy with the Presidential letterhead upon it. Below it, in blue ballpoint scrawl, was my name, my passport number, my birthday and a series of villages I was to pass through on my way.

Shinkolobwe is now considered an official nonplace. The provincial governor had ordered a squad of soldiers to evacuate the village and burn down all the huts in 2004, leaving nothing behind but stumps and garbage. A detachment of Army personnel was left behind to guard the edges and make sure nobody entered.

The government had been embarrassed by a series of accidental deaths inside the mine. Some men were digging inside a jerry-built tunnel when it collapsed on them. Eight were killed, and thirteen injured.

Fatal accidents are all too common in the illegal mining trade of the Congo. Abandoned mines like this one are scattered all over the southern savanna and most of them are still being picked over by local farmers hoping to boost their income by selling a few bags of minerals on the side, usually copper and a smattering of cobalt. Shinkolobwe was different. This was the pit which, in the 1940s, had yielded most of the uranium for the atomic bombs the United States had dropped on Hiroshima and Nagasaki.

But it was more than historical curiosity. The pit had been closed and the mineshafts sealed tight with concrete plugs when Congo became an independent nation more than four decades ago, yet local miners had been sneaking into the pit to dig out its radioactive contents and sell them on the black market. The birthplace of the atomic bomb is still bleeding uranium and nobody is certain where it might be going.

Shinkolobwe is in the midst of a pleasant savanna of hills and acacia trees in a region called Katanga, where people have been farming more than two thousand years with tools made from wood and copper picked from the ground. This place, and the rest of the Congo, had been the private preserve of King Leopold II of Belgium, who had claimed the territory for himself when the European powers were beginning to plant their flags around Africa in the 1870s. Leopold promised to run “this magnificent African cake” for the charity and benefit of the natives.

Congo instead became a gigantic forced-labor camp. The Africans were threatened with brutal beatings and the amputation of their hands and even beheadings if they failed to collect enough ivory tusks or lumber to satisfy the quotas of Belgian managers. The government of Belgium took over the estates in 1908, preserving the system of forced labor under the rule of monopoly companies. The largest was a mining giant called “Union Minière de Haut Katanga” which started exploiting copper in the southern tail section. Delighted executives called it un scandale géologique – a “geological scandal”—and built an empire of mills, furnaces and rails in the bush. Locals were paid the equivalent of twenty cents a day to break rocks and push carts. It amounted to a version of debt slavery: taxes were kept purposefully high and workers were not permitted to select their own occupations. The men slept eight to a hut in settlements ringed with barbed wire to prevent them from leaving before their contracts were up. Typhoid and dysentery were rampant.

One of these sites had been Shinkolobwe, where patches of high-grade uranium had been found by chance in 1915. The workers were made to carry sacks of the velvety black stone – then used only for radium-based cancer cures -- more than twenty kilometers to the railhead, where they were sent to port and then shipped by ocean steamer to Belgium. The tailings were simply thrown away. By itself, it was considered worthless: a trash rock.

When the Nazis invaded Belgium in 1940, the company moved its headquarters to New York. The U.S. would soon become the world’s largest user of its cobalt, which was an important metal for the manufacture of aircraft engines. The Congo mines started operating around the clock. And by then, an ominous realization had began to dawn among a handful of scientists in European and American universities: that the overburdened nucleus of U-235 was just on the edge of cracking asunder and might be broken with a single neutron. The mine would go on to supply nearly two-thirds of the uranium used in the bomb dropped over Hiroshima, and much of the related product of plutonium that went into the bomb dropped on Nagasaki.

For the next two decades, Shinkolobwe enjoyed a mystique as the number-one producer of the most powerful substance on earth. “A freak occurrence in nature,” one Army colonel called it. “Nothing like it has ever again been found.” Access to the site was forbidden, and the closest a visitor could get was to see the giant block of pure uranium the company put on display in the nearby city of Elisabethville. Visitors were warned not to get too close with their cameras, lest their film be fogged and ruined. A sign said: Attention. Bloc Radioactif!

The Belgians had expected to rule their colony for more than a century, but increasing violence in the capital convinced them to step aside and grant Congo its independence in 1960. With American backing, a 29-year-old army officer named Joseph Desiree Mobutu seized power in a coup and would, over time, set himself up as a secular messiah even as he looted the nation as systematically as King Leopold. He took a cut from virtually every business in his country, siphoning off $4 billion, and building luxurious marble palaces for himself all over his dirt-poor country. The once-promising economy went into a tailspin. Roads fell apart. Farms dehydrated in the equatorial sun. Union Minière’s property was nationalized, and then looted.

But not Shinkolobwe. The managers feared that such a lethal substance would fall into the wrong hands. They poured concrete into the shafts and carted off the equipment. Scavengers tore the metal from the uranium warehouses. The worker’s village was evacuated and sealed off, and weeds began to sprout inside the shells of brick townhouses. Mango trees drooped, nodded and eventually toppled onto the deserted streets. Shinkolobwe crept back, day after day, into a state of nature.

The place does not appear on most local maps, but is not difficult to find. I hired a translator and we rented a Toyota Land Cruiser for a few hundred dollars in the city of Lubumbashi, once called Elisabethville, the principal railhead for most of the ore trains that used to run to the Atlantic. The city’s economy still thrives on minerals, both legal and bootleg. Chinese companies have established a strong presence as buyers of the copper and cobalt picked out of the open pits.

We left the city at dawn and headed north, on a potholed national highway that faded into dirt, through forests of eucalyptus and acacia. My translator turned onto a rutted side track in the hilly country north of Likasi and we quickly got bogged down in the mud. A farmer came to help push us out; a man named Alphonse Ngoy Somwe, who told us that he had worked as a miner at Shinkolobwe, where copper was usually the big thing. There had been at least one time, however, when he had looked for uranium. A few years ago, he recalled, some white men had come to buy their ore and had waved electronic devices over the rocks. He said he didn’t want to do mining anymore – “it kills” – but after we pushed the Toyota loose, he agreed to show us the way.

We bounced through a small village with a Pentecostal church made out of poles and grass and, shortly thereafter, came to a spot where the road took a plunge into a rocky valley; too precipitous for the Land Cruiser to handle.

Sowme told us the mine was about seven kilometers further. I shouldered my pack and we all started walking.

A substantial amount of uranium has been smuggled out of Congo in the last decade, and the source is almost certainly Shinkolobwe.

In October of 2005, a customs official in Tanzania made a routine inspection of a long-haul truck carrying several barrels of a metal called columbite-tantalite, otherwise known as coltan, a rare metal used in the manufacture of laptop computers and cell phones and other electronic goods. But he found a lode of unfamiliar black grit instead.

One of his bosses later recalled the scene to a reporter: “There were several containers due to be shipped and they were all routinely scanned with a Geiger counter. This one was very radioactive. When we opened the container it was full of drums of coltan. Each drum contains about fifty kilograms of ore. When the first and second rows were removed, the ones after that were found to be drums of uranium.” A United Nations panel came in to investigate and concluded the source of both shipments had been illegal mining at Shinkolobwe.

The clandestine mining of uranium is not hard to conceal in the midst of so much other petty corruption. In most of Union Minière’s abandoned pits, there is an active hunt for what is called “Congo caviar” – the rich mineral blend of cobalt and copper harvested by scavengers and purchased by speculators. This activity is supposed to be illegal, but it has been widely tolerated for more than a decade. The miners work in T-shirts and flip-flops and dig out the chunks of caviar with shovels, picks and their bare hands. Approximately 50,000 to 70,000 people are doing this on any given day. The cobalt is particularly prized and fetches high prices. It is a vital metal in the construction of jet engines and turbines. Energy-hungry China is a primary buyer. But in the majority of cases the minerals leave the country illegally, without being recorded and without being taxed. The usual route is through Zambia. And at every step in this unofficial process, from the mine to the border, successive layers of police and inspectors demand a cut.

A common joke among nuclear policy analysts is that the best way to move an atomic bomb across a national border would be to hide it inside a truckload of marijuana. In other words, smuggling routes used by average criminals provide good cover for the occasional piece of nuclear merchandise.

Fueled by a rising worldwide interest in nuclear power, the price of uranium soared in 2007 and in the rush to put old fields back into production, a company called Brinkley Mining signed an agreement in 2007 with the Democratic Republic of Congo for the exploration and exploitation of Shinkolobwe, where the supply of uranium seemed to be bottomless.

As a bonus to the Congo – and perhaps a sign of eagerness – Brinkley also pledged to help fix the dilapidated nuclear reactor in Kinshasa and install radiation detectors to keep stolen uranium from leaving the country.

The deal soon fell apart. Police in Congo arrested two of Kinshasa’s top nuclear officials and accused them of conspiring in a criminal plot to illegally export the country’s uranium. The pair were released from jail within the week, though kept under investigation. A deputy mining minister said the leases were invalid. “Uranium is a reserved mineral,” he told a reporter. “We want to leave it for future generations.”

The mystery of the illicit buying continued. There was no accounting of how many bags of uranium might have left Shinkolobwe under a truck tarp and smuggled through Zambia to places unknown. A few Western diplomats suggested that purchasing agents for Iran may have been the ultimate buyers. It might also have been elements of the A.Q. Khan sales network, or terrorists looking for shrapnel in a dirty bomb.

A more banal possibility, and one more likely than any of these, is that it was simply hoarded up by a speculator waiting for a buyer to come forward, much as the Belgian company had patiently awaited a visit from the U.S. Army in the 1940s. The uranium could not be fashioned into a weapon all by itself, but it might be useful to a state with nuclear ambitions. The purloined ore could be fed into a graphite-moderated heavy water reactor, such as those now located at Khushab in Pakistan or Arak in Iran, or even Cirrus in India, which can run on natural uranium. Though this would be a cheaper path to a bomb than conventional enrichment, such a scheme would require a campus that would be hard to conceal from spy satellites. At a minimum, there would have to be a yellowcake mill, a fuel fabrication plant, a reactor and a sophisticated reprocessing shop with glove boxes, precision gear and tubs of nitric acid. A nation which attempted such a cut-rate Manhattan Project would face formidable barriers. They would need millions of dollars and the unpredictable factor of luck. But seventy years of history has shown that nations are willing to make extraordinary sacrifices and challenge long odds to enter the club of the privileged. Nine nations have made the journey thus far.

If a speculator did take a flier in black-market uranium from Shinkolobwe, it would not be difficult to hide it from prying eyes. It could be barreled and stacked in an obscure corner of an industrial yard. It could be stored in a row of tin sheds in a forest. For that matter, it could simply be piled out in the open air, with the perfect disguise as a gravel heap. Rain or snow will not harm it. And its fissile potency will not substantially diminish until approximately seven hundred million years have passed.

After about two hours, we came to the ruins of a metal fence nearly covered in the jacaranda trees on the side of the road. There were a few bricks scattered about. It felt like we were walking through the leavings of a bygone civilization -- a garrison on the Roman frontier, perhaps, or one of the forgotten silver villas in the Andes. But this was antiquity of the atomic age.

We walked about a kilometer down a concrete road, past mounds of black dirt, old slag. This was the outer fringe of what had been the “B Zone,” the heart of the uranium mining operation run by the Belgians. Shards of iron pipe and green chips of oxidizing copper lay scattered on the path. To the west were the metal skeletons of what had been a warehouse and a water tower.

When we passed though a gap in the trees, a panorama suddenly opened. Across a wide clearing in the forest, it was possible to see a line of trees a mile away, across a low man-made canyon whose sides were stained black and brown and whose bottom held pools of cloudy green water. This was the Shinkolobwe pit, the womb of the atomic bomb. One a different side of the world, a quarter-million Japanese people had been killed with the material from this cavity. There were no freelance miners anywhere in sight, but the soil in the center of the pit had been thoroughly worked over. Broken wood slats were littered about the slopes, the remnants of jerry-built mine works.

The three of us stood at the edge of the pit and looked in for a while. None of us spoke. A few fat cumulus clouds drifted overhead.

We were there for several minutes before I realized that I still had the “letter of authorization” from the police official in my backpack. I hadn’t needed to withdraw it because we hadn’t encountered a single roadblock. Nobody was guarding Shinkolobwe. We had walked right in.

Reprinted by arrangement with Viking, a member of Penguin Group (USA) Inc., from URANIUM by Tom Zoellner. Copyright © 2009 by Tom Zoellner.