The ring is 30 feet in diameter with a great copper ashtray in the middle. Around the rim men sit and shout at each other every weekday.

They could be bookmakers at a race track or a big fight. In fact they are the dealers of the century-old London Metal Exchange. And although their methods seem strange their buying and selling of millions of dollars worth of nonferrous influential free market price for copper, tin, lead, zinc and silver.

"One hundred at eight," shouts a dealer - all bidding must be by "open outcry" across the ring. And 100 metric tons or copper at 708 pounds sterling a ton ($1,324) are on the move.

A clerk records the deal, others communicate how the market is going to colleagues on open telephone lines and on to brokers everywhere. The closing prices are flashed around the world.

The London Metal Exchange has survived despite attempts by Third World producers and large mining companies to bypass it, despite competition from other markets such as the New York Commodities Exchange and the fact that London has waned in world importance since the exchange was first set up.

"The [London] price is the most important in the world. That is what our friends say and I'm sure it is too." said Ivor Foster, chairman of the exchange. He sees it as an extremely sensitive price barometer responding daily to hundreds of influences in many parts of the world which comes up with a realistic expression of supply and demand.

Increased speculation, particularly by large offshore trusts buying metal and holding onto it as a hedge against inflation is one of the clouds over the exchange.

Cartels and price stabilization schemes from the United Nations Conference on Trade and Development (UNCYAD) are the other clouds on the horizon.

Members smile sardonically when the word cartel is mentioned. They talk of the time producers kept buying copper at 234 pounds sterling a ton between 1962-63. The fixed price, they say, was disguising economic forces which caused even greater instability when the price finally moved.

The international tin agreement "ceiling" has not held in times of scarcity and attempts to set and hold a European zinc price have had only limited success.And UNCTAD will never work, they say.

"If you throw bureaucrats and politicians into it suddenly you have a vested interest, the market will be thrown out of gear and you will not have a realistic price. I have great faith in politicians to bugger up everything they touch," said Foster.

The London metals exchange is often accused of causing unnecessary price fluctuations and that brokers get their living from movements and therefore have a vested interest in them. Members say the daily fluctuations make for greater underlying stability.

The London price can make frontpage headlines in countries like Chile, Peru and its price is used as the basis for direct supply contracts all over the world, apart from North America. But even there its influence is felt.

To the 29 companies who are members of the ring it is a very exclusive club with rigid standards of membership and behavior.

Suits and ties must be worn and fines are imposed for swearing, smoking during the main dealing sessions, and even for being on the premises after 5 p.m. (Visiting Syracuse University journalism students got told off for opening newspapers during dealing which is also forbidden.)

Members like to say a seat on the ring costs nothing. Membership is by election and a new member might have to show up to 5 million pounds in assets and much more importantly know about, and be known in, the metal trade and respected for integrity. It is a close-knit world with a language of its own.

Members points to several characteristics that explain why their market has survived and is still influential, even though only around 5 percent of the world production of the metals involved are physically traded there.

It is physical market. The London exchange actually has the metal in more than 50 warehouses in such places as Rotterdam, Hamburg, Antwerp and Bremen as well as in Britain. The contracts are for delivery any market day up to three months ahead - the time ships used to take to reach Britain from the producing countries. Moreover, it is the only source of metal supply that issues contracts that have no force majeure provision - a strike or an act of God is no excuse - The metal contracted for has to be delivered.

Between 70 and 80 percent of the trade comes from outside Britain. Members argue this makes for a more representative price.

"Just look at what happens to the minor metals not traded" here, said one former exchange chairman. Before the end of the year the exchange will almost certainly add aluminum to its list of traded metals.

The chief economist for an international mining company said he saw the influential position of the exchange continuing. Antitrust legislation in the United States and European Common Market regulations were making price fixed more difficult.

Foster is even more bullish "it has lasted 100 years and I think it will last 300 because it is needed by the trade. Nothing better has been invented - and if it could it would have been."