If you're holding some of the estimated 20 million gold Krugerrand coins sold in the United States, there is no reason to panic and sell just because the government may ban the import of new coins from South Africa. It will remain legal to buy, sell and hold the coins already here. As a long-term gold investment, your present Krugerrands are as good as any.

But if you are thinking of buying gold coins today, dealers advise you to choose the Canadian Maple Leaf instead of the Krugerrand. Both contain one ounce of fine gold, and the Maple Leaf carries no political risk.

The price of gold ($321 an ounce last week, near its recent lows) will rise if inflation rises over the next year or so. Conversely, the price probably will fall or go nowhere if inflation stays flat or a recession develops. But if hyperinflation ever hits the United States, gold would be one of the few investments to see you through.

Maple Leafs and Krugerrands are known as "bullion coins" -- meaning that they sell as a pure gold investment (as opposed to rare gold coins, whose much higher price is based on their scarcity and artistic merit).

Bullion coins typically sell for 5 to 10 percent more than the value of their gold content, depending on the size of your order and the dealer you choose. That extra premium effectively covers the cost of the coins' manufacture.

When you resell your gold coins to a dealer, you generally can expect to be paid about 3 percent over the gold price, minus a sales commission. So when you make a gold-coin investment, the price of gold must rise by a modest amount before you'll break even on the deal.

Maple Leafs and Krugerrands usually sell for about the same price. But in recent months, speculators have been dumping South African coins and driving down the price. Krugerrands now sell for just a touch over the underlying gold price at many dealers; if you resell, you might get the gold price or less, after sales commissions.

Why did the speculators sell? Because gold-coin investors always want the freest possible market. The political activists who have been picketing gold-coin shops have persuaded many dealers to quit handling Krugerrands (temporarily, at least), which is making those coins a little harder to sell. Hence the decision by many investors to dump. But there's no reason for long-term investors to follow the crowd.

In fact, the relatively low price on Krugerrands even has caused some dealers to recommend their purchase, if conscience allows. "There will always be a market for them," one New York dealer says. "After the smoke clears, the price may go back up by 1 or 2 percent."

Two other gold bullion coins now on the market contain exactly one ounce of fine gold: the Mexican Onza and the Chinese Panda. Pandas usually are priced a little higher because fewer of them are minted. Generally speaking, the more you pay over the underlying gold value, the higher your investment risk.

Of the small gold bars sold by many dealers, those made by Engelhard and Credit Suisse generally are considered the easiest to resell. But small bars often carry a lower resale price than gold coins of the same weight, which makes the coins a better buy.

Investors should pay attention to the size of the sales commission, as well as to the price of the coin itself. Some dealers charge a lot more than others.

The boiler-room telephone salesmen have come out in force to take advantage of the political upheaval over South African gold. They tell you that gold is sure to go up and urge you to buy, today, at their special price. Unfortunately, their special price is usually substantially higher than you would pay at any reputable brokerage house or gold-coin shop in town.

In the major scams, the salesman takes your money, sends you a piece of paper supposedly representing a gold investment, but never buys you any gold. By the time you're demanding your money back, he's out of business and selling certificates under another name to yet another crop of naifs.

Although gold is in the news, a major telephone-sales business is being done today in the common silver dollars minted before the United States debased its coinage.

Rare-coin dealer David Bowers, of Bowers and Merena Galleries Inc. in Wolfeboro, N.H., says that the telemarketers are charging about 50 percent more than you'd pay at a coin shop. For worn common coins that ordinarily cost $14 to $15, the telephone salesmen are likely to charge $30 or more. For 19th-century silver coins, dealer-priced at $55 to $60, some telemarketers are charging $85 to $90. So buyer, beware.