THE LAST TIME U.S. Mint officials launched a set of coins in Washington, they trucked two huge baby blue coin presses from Philadelphia and parked them alongside the U.S. Capitol. The resulting ceremony attracted a lot of media attention, but sales of the new coins, commemorating the 200th anniversary of Congress, were poor.

Friday Mint officials will try again. At 10 a.m. they will assemble at Ford's Theatre to begin sales of this year's major commemorative coin set, the three coins that mark the 50th anniversary of the Mount Rushmore National Memorial.

Unlike the ceremony for the 1989 congressional coins, the event will not be a "first strike" ceremony, with the secretary of the Treasury symbolically minting the first coins in the series. Instead, the Washington event is being heralded as an "unveiling" of the actual coins and the start of a drive to raise up to $18.7 million for the monument through sales of the commemoratives.

"We had been hearing from some of our old friends that our first-strike ceremonies are nice, but that they are getting a little old hat," said Mint Director Donna Pope. Mint officials first considered a ceremony at the South Dakota memorial, but prospects of bad weather and the likelihood of relatively little news coverage by the national media brought them back to Washington.

The result will be a ceremony bringing the memorial to Washington. As a host of South Dakota officials look on, Mary Ellis Borglum Powers, daughter of sculptor Gutzon Borglum, is expected to recall the 14 summers she spent with her father as he created the memorial to George Washington, Thomas Jefferson, Theodore Roosevelt and Abraham Lincoln on the side of one of the Black Hills.

"You were overcome by its greatness, but you didn't stop to analyze it because it was part of our life and part of our family," she has said.

Pope is hoping the memorial's popularity -- it gets 2 million visitors a year -- will make the coins "the most sellable" of three commemoratives the Mint will issue this year. With commemoratives due later in the year for the United Services Organization (USO) and the Korean War, Pope said it is "hard to project a sellout," but she hopes the Mount Rushmore coins may raise $14 million for the memorial.

Most collectors know there is another reason to order the coins early. All orders postmarked by March 28 qualify for discounted pre-issue prices that offer substantial savings over the regular price. That incentive traditionally stimulates the early sales of most commemoratives and gives Mint officials an early idea of how successful the coin offering will be.

Preliminary designs for the three Mount Rushmore coins were disclosed last year when they were presented to the Commission of Fine Arts, the federal panel which reviews all coin designs before they are ordered into production.

The Mount Rushmore coins, being sold in proof quality sets at a pre-issue price of $225, include:

A $5 gold coin minted at the West Point, N.Y., mint. The coin's face shows an eagle in flight over Mount Rushmore and its reverse carries the lettering "Mount Rushmore National Memorial."

Congress authorized up to 500,000 of the gold coins to be minted. The coins weigh 8.359 grams and are 90 percent gold. They will sell for a pre-issue price of $195 each in proof quality and $185 in uncirculated condition. The price includes a $35 surcharge to be split between the memorial and reducing the national debt.

A $1 silver coin that weighs 26.73 grams and is 90 percent silver, 10 percent copper. The coin's face features a view of the memorial surrounded by a laurel wreath, and the reverse has an eagle's crest over an outline map of the United States marking the memorial's location. Up to 2.5 million of the silver dollars are authorized with a $7 surcharge.

Proof versions of the dollar, which will sell for $28 each, will be minted in San Francisco. Uncirculated versions, which will be offered for $23, are being struck in Philadelphia.

A half dollar made of 91.67 percent copper and 8.33 percent nickel that will weigh 11.34 grams. It will sell for $8.50 in proof quality and $6 in uncirculated condition, a price that includes a $1 surcharge. The proof half dollars are being struck in San Francisco and the uncirculated coins in Denver.

The half dollar's face features another view of the memorial with a sunburst and the reverse features a view of an American buffalo.

INFORMATION on purchasing the Mount Rushmore coins is available from the Customer Service Center, U.S. Mint, 10001 Aerospace Dr., Lanham, MD 20760. Call 301/436-7400 or 800/545-1111.

Bill McAllister is a member of The Washington Post national staff.