The customers who stroll into the Deak-Perera precious metal store on K Street in downtown Washington often gravitate to the display of shiny gold coins in the front lobby. The coins are Krugerrands, minted in the Republic of South Africa, and they're the most popular items in the shop.

"Everybody buys Krugerrands," says Bernard Zeng, the store's manager. "That's the greatest thing about them. . . . If you're shopping for your wife or daughter or niece, they make a wonderful Christmas gift. You're buying for the future."

It is also an investment that has become a cause celebre in the mounting debate over South African apartheid. About $450 million worth of freshly minted Krugerrands were purchased by Americans last year, making the little gold coins the biggest single U.S. import from that country, outstripping our buys of such strategic South African minerals as chrome, platinum and uranium.

"They're a symbol of South Africa," said Rep. Stephen Solarz (D-N.Y.), who has been working for more than two years on legislation to outlaw Krugerrand imports. "Banning Krugerrand imports is one creative way of applying pressure on the South African government to eliminate apartheid."

Yet the Krugerrand issue also illustrates the political difficulties in passing most U.S. sanctions against the defiant South Africans. Solarz first succeeded in getting his Krugerrand bill through the House more than a year ago. But so many Americans have bought and sold Krugerrands -- an estimated 5 million U.S. citizens now own them -- that they constitute a formidable economic lobby in their own right.

Precious-metal dealers, investment counselors, and wealthy California-based "gold bug" and conservative activist Howard Ruff mounted a massive protest campaign against the Krugerrand amendment last spring. Employing state-of-the-art computer technology, Ruff's Washington lobbying organization, called Free the Eagle, flooded Capitol Hill with overnight telegrams on behalf of thousands of Krugerrand owners.

The campaign ultimately was successful in killing the provision, but Ruff did not let up. During last fall's election campaign, his political action committee contributed $10,000 to Solarz's Republican opponent and spent an additional $17,000 in independent expenditures against him, helping to slice in half the margin of victory for the five-term Brooklyn Democrat.

Now both sides are gearing up for another donnybrook when Congress convenes next month.

"We argue that this is a travesty," said Neal Blair, the top Washington lobbyist for Ruff's organization. "If they can ban the Krugerrand, they can start restricting our freedom to invest in other ways. . . . We're in this because we try to look out for hard money."

Like many defenders of the right to buy Krugerrands, Blair argues that banning their import would be counterproductive. The South African government would still enjoy a worldwide market for its gold bullion, he says, but overall gold production might drop and some South African blacks would be thrown out of work.

"There are thousands of blacks migrating into South Africa to work in the mines there," said Blair. "As repressive as conditions are over there, they are voting with their feet. . . . Some of these people [who want to ban the Krugerrand] have malicious aims. They want to topple the government. They're really not interested in helping the black. They're using this as a ploy."

In many ways, the Krugerrand battle mirrors the debate over South Africa on other fronts, most notably the effort to pressure U.S. corporations to pull out of the country. But this one is infused with its own special flavor: the enduring mystique of gold.

What the late English economist John Maynard Keynes once called "that barbarous relic" is still, for millions of investors, the only "real" money -- a safe financial haven in an age of political turmoil and economic uncertainty. In 1979, when the Iranian mullahs overthrew the shah and double-digit inflation ravaged American consumers, gold prices soared to $850 an ounce, and Krugerrand sales boomed.

"This is not a pretty world to live in," explained Zeng, the Deak-Perera metals dealer. "But you should insure against it. That's what a majority of my Krugerrand customers want to do."

Nobody benefits from this form of investor anxiety more than the South Africans, who control half of the world's gold reserves and accounted for 21.8 million of the 44.5 million ounces of gold mined last year. Seventeen years ago, in search of a new market for their most precious product, the South African government and the country's six big mining companies came up with the idea of issuing a coin commemorating Paul Kruger, the "George Washington of South Africa" whose 19th century racial theories were bequeathed to his Afrikanner countrymen.

"The black man had to be taught that he came second, that he belongs to the inferior class that must obey," Kruger once said.

The Krugerrand was an instant hit, largely because it was the world's first gold coin that was exactly one ounce, making it a handy purchase for investors.

"Governments have been minting gold coins for thousands of years," noted Henry Jarecki, chairman of Mocatta Metals Corp., a New York-based precious metals dealer. "But what the South Africans did -- where they were the leaders -- was in minting the coin at one ounce. That made it easy for a guy to look in the paper and know exactly what he's got. Telling a guy that he owns 1.2506 ounces for gold sometimes doesn't help him very much."

Today, the marketing of the Krugerrand is a thriving worldwide enterprise that is conducted by International Gold Ltd., an arm of the South African Chamber of Mines that oversees U.S. sales out of offices in New York and Los Angeles. Michael Vigil, Intergold's deputy chief executive officer in New York, emphasized that, unlike gold bullion, Krugerrand profits do not flow to the South African government. Instead, they go to the Chamber of Mines, whose largest member is the Anglo-American Corp. of South Africa, the huge minerals conglomerate controlled by industrialist Harry F. Oppenheimer.

"The irony of this is that the sale of the Krugerrand benefits private industry, while the sale of gold bullion benefits the government," said Vigil. "So if anything were to stop the sale of the Krugerrand, the South African government would just sell more bullion."

Nevertheless, Intergold's high-profile marketing efforts have made the coin a tempting target for anti-apartheid activists. The New York advertising firm of Doyle, Dane, Bernbach International, under contract with Intergold, promotes the Krugerrand with ads in leading publications, such as the Wall Street Journal. Hundreds of banks, brokerage houses and metal dealers sell the coins in small towns throughout the country.

"I think we're going to see a new surge of pressure against the Krugerrand," said Tim Smith, executive director of the Interfaith Center on Corporate Responsibility, an anti-apartheid coalition of church groups.

"The Krugerrand is something that people all around the country can picket," he said. "Because if you have a Deak-Perera or a brokerage house or a bank, you have a symbol of South Africa right there in your back yard."

So far, some financial houses, such as Merrill Lynch, Shearson Lehman/American Express and Dean Witter Reynolds, have responded to the pressure and agreed not to carry the Krugerrand. But Deak-Perera manager Zeng is holding out. "What we're offering is a financial service," he said. "We're really responding to a demand from the public." CAPTION: Picture 1, U.S. Citizens bought $450 million in Krugerrands last year; Picture 2, Unlike gold bullion, Krugerrand profits do not flow to South African government. By Ken Feil -- The Washington Post; Picture 3, Coin is the biggest U.S. import from South Africa, outstripping strategic minerals. By Douglas Chevalier -- The Washington Post