The U.S. Mint earlier this year lost 24 dies used to strike American gold coins in an incident that Rep. Frank Annunzio, D-Ill., calls "inexplicable," "inexcusable" and "unpardonable."

Annunzio, chairman of the House Banking subcommittee that oversees the Mint, said the Mint in January tried to ship the dies, used to strike 1-ounce gold bullion Eagles, from the San Francisco mint to the West Point, N.Y., mint via an overnight mail service."Incredibly, the mint failed to require that the dies be shipped under even signature control," Annunzio said in a speech on the House floor. "They were shipped as ordinary freight, as if they were a crate of oranges."

They never arrived and are still missing, he said.

It was the second such mishap in two years. In April 1986, a shipment of 44 dies used to strike the $1 Statue of Liberty commemorative coins disappeared en route to the Royal Canadian Mint in Ottawa.

Annunzio said he planned to question Mint officials about the latest incident at budget hearings of the subcommittee later this year.

"I intend to find out why security for dies was so deliberately lax," he said. "Losing dies once because of slack shipping procedures is inexcusable; losing dies a second time is unpardonable."

The coins have a face value of $50, but currently sell for between $460 and $470, depending on the spot price of gold. The dies are worth about $40 each, said Michael Brown, a spokesman for the Mint.

Brown said Thursday the missing dies likely would be of little use to counterfeiters because all of the dies were for the front, or face, of the coin.

The Secret Service and the shipping company are investigating. Apparently, Brown said, a clerk in the San Francisco mint failed to complete a shipping form that would have required Federal Express employees to sign for the dies at each transfer point.

The clerk has not been disciplined, Brown said, but added, "We're working on that process right now."

Brown said the Mint has been using Federal Express since 1983 and shipped 350,000 dies domestically without incident. Since late April, armored cars have been used.

"I think our record's pretty good. . . . Obviously it was a mistake, and we don't like them to happen and we moved quickly to make sure it doesn't happen again," he said.