For rocks that are larger than a baseball, he added, "people find they get more money by carving it up and selling it in smaller pieces".
Meteorite fragments are not radioactive or dangerous, said Palma, unless they have just landed, when they might be blistering hot.
The lucrative price for meteorites - and the fact that rocks collected from national parks and other public land in the US are supposed to belong to the federal government - has created a thriving black market worldwide.
In 1998, as a special agent with NASA, Gutheinz led an undercover sting operation that was designed to catch people selling phony moon rocks. Instead, Operation Lunar Eclipse led him to a man who had a real moon rock and an asking price of $5 million.