A group of silver investors filed a $194 million lawsuit yesterday accusing the two big silver markets and major silver dealers of fraud, conspiracy, violating antitrust laws and manipulating the price of the metal when silver prices collapsed two years ago.

The lawsuit was filed in U.S. District Court in New York by 184 members of Free Market Compensation, a Boston-based organization that contends silver market insiders conspired to drive down silver prices in the spring of 1980.

Defendants in the case are the Commodity Exchange Inc. (Comex) of New York and the Comex Clearing Association, the Chicago Board of Trade and its clearing association and five silver dealers--Englehardt Minerals and Chemicals, Mocotta Metals Corp., Ametalco Inc., Sharps-Pixley Inc. and J. Aron & Co. and one of its affiliates.

The lawsuit is the third legal action filed in the past week charging that federal laws were violated during the dramatic rise and fall of silver prices in 1979 and 1980. A Minnesota investor, David Bishop, sued Comex earlier this week.

Last Friday, a Lichtenstein corporation, Wall Street Establishments, filed an $8 million lawsuit accusing Texas billionaires Nelson Bunker Hunt and W. Herbert Hunt, the Comex and the Chicago Board of Trade of rigging silver prices.

The lawsuits are being filed now to meet a two-year statute of limitations. It was two years ago today that Comex ordered a change in its rules that prohibited new buyers from coming into the silver futures market and forced those already in to sell some holdings.

The price of silver hit a record $50 an ounce on Jan. 21, 1980, then plunged steadily until it bottomed out at $10.85 on March 28, wiping out billions of dollars of paper profits for silver speculators, including the Hunts.

The Comex claimed the change in rules was necessary because the Hunts and a few other speculators had acquired vast numbers of silver futures contracts and were artificially inflating the price.

The Hunts, on the other hand, repeatedly have accused silver market insiders of changing the rules of the game and forcing prices down to further their own interests.

The Hunt brothers are not among the 184 silver investors who filed the $194 million lawsuit yesterday, but the plaintiffs--like the Hunts--all held silver futures contracts at the time the market collapsed. Brian Walsh, president of Free Market Compensation, insists his group is not a front for the Hunts.

The lawsuit repeats arguments made by the Hunts and utilizes a costly study financed by the Hunts that alleges the silver dealers and Comex directors stood to lose $2 billion unless prices went down.

The lawsuit accuses the silver market insiders of violating the Sherman Antitrust Act and the Commodity Exchange Act as well as "common law fraud, conspiracy to manipulate and fix prices, restrain trade and defraud" investors.

The lawsuit seeks $48 million in damages, asks that amount be tripled under antitrust laws and asks $50 million punitive damages.

Changes in silver trading rules on Jan. 7 and Jan. 21, 1980 caused prices to collapse, the petition contends, and permitted "the members of the Comex and its board of governors to reap tremendous profits."

The rules changes were voted by the Comex board, which included representatives of the big metal dealers. The dealers involved did not vote on the rules change and therefore have insisted there was no conflict of interest by the board.

But Walsh's group contends the board was protecting its own members, even if they did not vote on the particular rule change, and even Comex board members who were not in the silver market had a conflict of interest because of their membership in the Comex Clearing Association. The Clearing Association is a separate but related corporation that handles the paperwork.

Contributing to this story was special correspondent John Kennedy.