BOLIVIANS call it simply ``the Rich Hill,'' or in Spanish Cerro Rico. It is a statement of the obvious. The top 1,000 feet of the 16,000-foot, rust-colored mountain are crammed full of silver. Cerro Rico is the world's largest known silver deposit. Its reserves are valued at an estimated $6 billion, easily more than Bolivia's $4 billion debt. And that is what was left by the Spanish after they took 60,000 tons of silver from the hill to feed their empire in the 16th and 17th centuries.
But local people in the city of Potos'i, tucked under the hill, are fiercely opposed to what they fear may be a second foreign plunder of their Cerro Rico.
A recent year-long study by the United Nations has shown that the hill still has at least as much silver as the Spaniards took out. But Bolivia has neither the capital nor the technology to exploit it. Companies from the United States, Canada, Australia, and Britain are aware of that, and several have made recent visits to check out the hill.
``There are several major companies who would love to get involved in Cerro Rico,'' says Charles Bruce, vice-president of the La Paz-based mining consultancy Mint. ``But the government would have to give a clear signal it wants them.''
A new mining code approved this month by Bolivia's Congress is designed to encourage international companies to tap the country's vast mineral wealth. But Mr. Bruce and other experts say there are several obstacles to foreigners touching Cerro Rico.
``The only feasible way to mine the hill is to use open-pit methods,'' says Enrique Arteaqa, a UN mining expert. ``But that means changing the shape of the hill.''
But to Bolivians, the idea of taking the top off the hill is anathema, roughly equivalent to defacing the Statue of Liberty, local people say. The familiar cone-shaped Cerro Rico appears on the Bolivian national flag, on Bolivian coins, and on Bolivia's coat of arms. The UN has also declared the hill a monument to humanity.
``How would Parisians react if someone asked them if they would be prepared to see the pillars of the Eiffel Tower destroyed?'' asks Victor Villanueva, who got to know most of the 600 miles of tunnels inside the hill in his 25 years as a miner.
But local miners have another reason for opposing multinational companies coming to mine the hill. A second silver boom would only line the pockets of foreigners, they fear, as happened with the Spanish.
``Potos'i has had a bitter experience of mining,'' says Wilson Mendista, a local historian. ``It was the second largest city in the world at the height of the silver boom - larger than London, Paris, or Seville. But now it is one of the world's poorest.''
While thousands of Indians died extracting the silver, the Spanish lived in luxury. There was so much silver that horses were sometimes shod in silver. For religious festivals, entire streets had paving stones replaced with silver bars.
But virtually none of the wealth stayed in Potos'i. Ornate church facades are the only reminder of the city's past splendor. Now the region around Potos'i is the poorest in Bolivia.
``It wouldn't be an exaggeration to say 170 out of every 1,000 children born in Potos'i die before they are five,'' says the Rev. Jaime Bartroli, a Roman Catholic priest who has worked for more than 20 years in the area.
The miners in Potos'i became even poorer after 1985 when the price of tin, the metal which replaced silver this century as Bolivia's chief export, collapsed on the world market. Nearly 2,000 local workers lost their jobs. Most swelled the ranks of the estimated 10,000 self-employed cooperative members who work the 3,000 passageways inside the hill.
The grim conditions down the mine have not changed much in 400 years.
``The cooperatives work in virtually the same way as the Indians under the Spanish,'' Mr. Villanueva explains. ``The miners now use carbide or electric lamps, whereas before they used fat from llamas. But they still extract the mineral by hand, they eat once a day, they talk the same language, and they earn on the basis of an advance.''
If he does well, a cooperative member can pick up $3 a day by scratching at the exhausted ore seams for zinc and silver. ``At least we can scrape a living at present,'' says Humberto Hinaosa, a member of the Kunti cooperative, one of 33 such groups that are working the hill.
``But if the price of zinc and silver continues to drop,'' Mr. Hinaosa says, ``we will have to go and grow coca.''
The Kunti cooperative's greatest fear, however, is the steep social cost of a foreign company mining Cerro Rico. Thousands would lose their means of survival. ``The city which has given so much to the world, now has so little,'' Hinaosa says. ``We don't want that repeated.''