(FORTUNE Magazine) – The bull market has been on a four-year romp and you may want to quit while you're ahead. Some experts recommend that you shift a portion of your winnings into gold. If that appeals, consider taking a fresh approach by buying stock in the Bank for International Settlements in Basel, Switzerland. The stock has long fluctuated with the price of gold, though with less volatility and less downside risk. And the BIS, unlike sterile bars of bullion, is a thriving institution that earns profits. Established in 1930, the BIS acts as a central bank to 80 of the world's central banks -- taking their deposits, lending them money, and investing in money market instruments. A model of conservatism, the BIS requires borrowing banks to put up super-safe collateral for loans, including plenty of gold. By a quirk of history, some 75,000 of the BIS's 473,125 outstanding shares are traded publicly in Basel and Paris. When the bank was organized, participating central banks were allotted shares. The U.S. Federal Reserve joined but refused to buy a stake, partly because it feared a conflict of interest from owning shares in a profit-seeking organization. The Fed's unclaimed securities were offered to the public, and recently investors could buy them for $4,800 each. Swiss Bank Corp., which sells BIS stock in the U.S., charges a commission of $48.74 on one outsize share. Those shares represent precious metal. Nearly a quarter of the bank's assets are in gold bullion, which the bank carries on the books at $208 an ounce. Gold on the open market currently fetches $340 an ounce. ''At its market value, the BIS gold alone is worth $4,500 a share,'' says James Grant, editor of Grant's Interest Rate Observer, a New York-based financial newsletter. Short-term money market instruments and other liquid investments bring the bank's adjusted book value to $6,500 a share. And while you wait for gold to move, BIS pays an annual dividend of $55 a share. The 1.1% yield is not much, but it's more than gold earns. Falling oil prices and low inflation would seem to militate against a dramatic rise in gold prices in the near future. However, some analysts say the political turmoil in South Africa could keep the metal rising. Gold surprised many investors by climbing 25% in 1985, and it has continued upward in 1986. Gold mining stocks have also been strong: Campbell Red Lake Mines, a Canadian company, recently sold at a dizzying price-earnings multiple of 42. Next to that, the BIS's multiple looks like a bargain: 17 times earnings per share in the fiscal year that ended in March 1985.

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