The world's best copper prospector

In the snake-infested jungle of south-eastern Ecuador, the American explorer David Lowell heard his head bounce off a rock "like a melon being hit by a hammer" as he slid down a waterfall.

Lowell was 72 and prospecting for copper that day in May 2000 when he stepped into a slippery stream bed for a vantage point free of vipers and vines. A broken rib and throbbing head sent him to a nearby hamlet in search of help.

"There was one man in the village who was a combination chiropractor and mortician," Lowell says. "We decided to just buy a little tin of liniment with the picture of a dragon on it." The expedition carried on.

Lowell had seen enough in the clear water of the stream to help him find one of South America's richest copper deposits. In May a joint venture of Chinese state-owned companies paid $US652 million to buy his partner in the exploration, the Vancouver company Corriente Resources, and he kept a stake for himself.

In a career spanning six decades and 44 countries, Lowell has made 14 major discoveries, including the world's largest copper deposit in Chile. He found treasures where others detected nothing worth mining, in the process revolutionising exploration. He made investors billions.

Now China is his biggest customer. State-owned companies paid $US1.5 billion for two of Lowell's biggest prizes, the riverbed of ore in Ecuador and a copper-filled mountain in Peru.

China's copper use is growing so quickly that by 2035 demand for the metal may outstrip supply by 11 million tonnes, according to CRU, a mining and metals consulting firm in London. That will keep Lowell's services in demand.

"He's a legend," says Marcel de Groot, chairman of Luna Gold in Vancouver, which retains Lowell as a consultant on a Brazilian mining project. "There's a lot of people who have plumbing and copper because of him."

Humans have been using the world's oldest metal in coins, cooking pots, pipes and roofs for 10,000 years. Today copper provides the electrical central nervous system for the cars, computers and microwaves that China cranks out for its 1.3 billion people and the rest of the world.

US copper production peaked at 48 per cent of world supply in 1945, and accounts for 8 per cent today. While the US economy is still almost three times larger than China's, Lowell says he worries America's reliance on finance and technology will stretch only so far.

"You also have to have the nuts and bolts - and the copper and iron, and the rare earths, and make copper wire and make television sets and make automobiles - to be important in the world," he says at his ranch in Arizona. Plaques and certificates cover a wall. The American Mining Hall of Fame inducted him in 2002 and the Australian Journal of Mining named him "World's Greatest Explorer" in 2004.

And Lowell is not through at the age of 82. Surrounded by a collection of antique mining lanterns, including a carbide lamp that saved his life in 1949, he says he is leading explorations in five South American countries. In a concession to age, they are mostly armchair expeditions.

His treasure hunting began at seven, when he hand-sorted silver samples in Arivaca, Arizona, for his father, Arthur Currier Lowell, a miner. Skinny, rebellious and indifferent in the classroom, Lowell says his mother, Lavina, considered him the least promising of her children.

His undergraduate degree was from the University of Arizona's College of Mines, and in 1957 he earned a master's in geology at Stanford University.

On his first job as a mining engineer in 1949, at a silver and lead mine in Mexico, Lowell survived a near-disaster that set the tone for his career. More than a kilometre underground, the waning flame in his carbide lamp signalled a life-threatening shortage of oxygen. Climbing a ladder to safety, Lowell lost consciousness and dropped the lantern, recovering it later.

Between close calls, he was taking note of mineral-formation patterns in large, low-grade deposits known as porphyry copper. Lowell theorised that porphyry formations share a common geology that can be used to detect commercially productive copper deposits. His observations would change the way prospectors read geological clues and led to some of mining's most spectacular finds.

The insight drew from understanding how copper-containing rock formed 150 million years ago, rising from the Earth's hot mantle on molten waves of magma called plutons. A bubble of water, silica, copper and gold formed at the tip of each mass as it migrated towards the cooler surface. Materials with the highest melting points solidified first and farthest down, creating a floor for copper, gold and other minerals, which cooled and crystallised in layers.

Copper is deposited along with some of these minerals in concentric rings, or halos, that can extend for kilometres and tilt at any angle, making the clues hard to see and interpret.

In 1965 Lowell was working as a consultant for Newmont Mining at its underground San Manuel copper mine in Arizona. There, the patterns "didn't make sense" unless the ore body had been turned on its side and severed by a violent realignment of the Earth's surface, he says. He surmised the deposit was part of a larger copper cylinder that had been sliced in two, leaving the rest to be found.

Newmont was not interested in this idea, Lowell says. So he sold the proposition to a unit of the Texas oil company Quintana Petroleum, founded by the late industrialist Hugh Roy Cullen. Lowell found the missing section. Quintana paid Lowell a finder's fee of $US120,000 and sold the find to Newmont in 1968.

The biggest strike came a decade later when Lowell was living in a tent in Chile's Atacama Desert, the driest place on Earth. This treasure hunt was for a partnership of companies later absorbed by San Ramon, Chevron and BHP Billiton.

Named Escondida, Spanish for "hidden," it is the world's biggest copper deposit. Two pits cover an area almost four times the size of New York's Central Park.

Escondida has yielded 16.6 million tonnes, worth $US138.2 billion at today's price, based on data compiled by the Chilean Copper Commission.

For finding Escondida and the adjacent Zaldivar copper field, Lowell was paid $US4.5 million. It was not until he met Catherine McLeod-Seltzer, a Canadian investment banker, at a party in Santiago, Chile, in 1992 that he began to leverage his mine-finding acumen into even bigger payouts.

McLeod-Seltzer, now 50, showed Lowell how to build publicly owned companies around his adventures. In January 1993 she followed Lowell to Peru and formed Arequipa Resources to sponsor and own his next project. That set up Lowell as chairman and a shareholder to profit from whatever he found.

While McLeod-Seltzer raised capital, he hunted for gold in Peru's Cordillera Negra range, which was occupied by Shining Path guerilla fighters. Three days after Christmas 1995 Lowell says he received laboratory confirmation of a major gold find. The following July, as he mapped out the claim, Barrick Gold in Toronto made a hostile takeover bid. Lowell says he drilled faster to expand the extent of the discovery and his company's value.

A month later Barrick raised its offer and bought Arequipa for $US790 million, an almost 30-fold increase in the shares' value from a year earlier. Lowell owned stock worth $US63 million, according to published accounts at the time. The deposit held about 8 million ounces of gold, Barrick says, worth $US11.1 billion today.

After five decades, Lowell says he went looking for a swan song in the records of undeveloped deposits. In his office in a converted barn, he pored over stacks of old technical reports that led him to a mountain in the Peruvian Andes known as Toromocho, Spanish for "the bull without horns".

In 2002 he visited the peak, 4500 metres above sea level. Mining deposits there had lain dormant since government geologists in the 1970s decided there was not enough copper to dig.

On May 14, 2003, Lowell paid the government $US2 million for an option on the property. From a bar in Lima, he phoned McLeod-Seltzer in the Canadian hospital where she was recovering from the birth of her first son. She named him Graham Jeffrey Lowell Seltzer in Lowell's honour.

Then she set up Peru Copper and raised $US12 million through a private placement to fund test drilling. In September 2004 the company generated $US48.2 million in an initial public offering. And in August 2007 Lowell sold Peru Copper to Aluminum Corp of China for $US810 million. Lowell's shares were worth about $US78.7 million, according to Securities and Exchange Commission filings.

Prospecting has earned more than $US150 million for Lowell and Edith, his wife of 62 years, based on interviews and securities filings. He says he has given most of it away, including his endowment of the Lowell Program in Economic Geology at the University of Arizona.

He is not through with hunting.

"If your primary purpose in life was finding sunken Spanish galleons full of gold and treasure, what would you do?" Lowell says. "I'm a professional treasure hunter."

Bloomberg