The fingertip-size piece of lunar material was given to the Honduran government by U.S. officials.
Broward County businessman Alan Rosen insists he got the ancient rock legally from a retired Honduran colonel. But the Justice Department says it was stolen and should be forfeited to the federal government. Honduras, which is not part of the court case, wants the rock back.
The rock was dug up by the Apollo 17 crew on the last manned moon mission and given by then-U.S. President Richard Nixon to Honduras in 1972. Federal agents seized it from Rosen more than four years ago.
"No one even knew it was missing until November 1998," Rosen's attorney Peter Herrick said. "What happened for 25 years?"
U.S. District Judge Adalberto Jordan must decide whether the rock was stolen to determine what to do with it. He heard the trial in two hours Monday and promised to rule in two to three weeks.
Rosen testified Monday that one of the country's dictators gave the rock to the Honduran colonel as a gift, and he has a contract with the colonel to sell it.
Rosen, who did business in Honduras for years, agreed to pay $50,000 and offered a contract in Spanish as proof of his legal claim.
He testified as the only trial witness that he has already paid $20,000 cash and handed over a refrigerated truck worth about $15,000.
Rosen said he set up a scientific authenticity test at Harvard University after talking to someone at the Smithsonian Institution about the rock. A Web site to promote the sale of the rock went online in 1996.
"Since I never believed there was a reason to hide it, I posted it," Rosen said.
Rosen said he believed the rock was worth about $5 million, based on a report that a moon rock given to the government of Nicaragua sold for $5 million to $10 million.
No one ever told U.S. customs agents about the rock when it was brought into the United States, a point stressed by Assistant U.S. Attorney James Swain as evidence that it was stolen.
NASA's position is that the only moon mission memorabilia — from the 842 pounds of excavated moon rock to spacesuit patches — that can be sold legally must have its backing or paperwork to prove its ownership trail.
Paperwork on the Honduran rock is missing between the U.S. gift and Rosen's sales contract.