Dakar, Senegal – the largest meteorite discovered on Earth – a 54-pound (25 kilograms) rock that fetched over $5 million at a New York auction last month, setting a world record.

However, in a West African nation where rusty red rocks have been excavated from the Sahara desert, authorities have initiated an investigation into what they describe as “illegal international trafficking,” suggesting it may have been smuggled from the country.

Here’s what you should know about meteorites and legal controversies:

How was it discovered

According to Sotheby’s, the rock, designated NWA 16788, was dislodged from the surface of Mars by a massive asteroid collision and journeyed 140 million miles (225 million kilometers) to Earth.

It was uncovered in the Sahara, northwest Niger by an unnamed meteorite hunter in November 2023, as per the auction house’s report. The identities of buyers remain undisclosed.

In the arid regions of the Sahara like Niger, meteorite hunting is on the rise. While meteorites can fall anywhere on Earth, the Sahara has emerged as a prime location for their discovery due to its climate, which is conducive to conservation.

Hunters often seek space rocks to sell to collectors and scientists. The most coveted and valuable meteorites are from Mars and the Moon.

As reported by the Heritage Academic Journal, the rock was sold to international dealers and eventually made it to a private gallery in Italy. Last year, a team of scientists from the University of Florence examined the rock to determine its structure and origins before it fell to Earth.

The meteorite was briefly showcased in Rome before appearing at the New York auction last month.

Why Niger is investigating

Following the sale, Niger raised concerns about how the meteorite was made available for auction.

Last month, the Niger government launched an inquiry into the discovery and sale of meteorites, stating that it resembles “illegal international trafficking.”

Last week, President Abdullah Hamanetiani halted the export of precious stones, semi-precious stones, and meteorites to ensure proper traceability.

In a statement to the Associated Press, Sotheby’s maintained that the meteorite was exported from Niger and transported in line with all applicable international regulations.

“In selling this item, all necessary documentation was obtained at each stage of the journey, consistent with best practices and the requirements of the involved countries,” the statement indicated.

Niger authorities did not respond to inquiries from the Associated Press.

What international law says

Patti Garstenblis, a cultural heritage attorney and expert on illegal trade, noted that rare minerals like meteorites are recognized as cultural property under the UNESCO Cultural Property Treaty, which both Niger and the United States have ratified.

However, Garstenbliss pointed out that Niger needs to establish ownership and that the meteorite was stolen.

“I doubt Niger could reclaim the meteorite if it wasn’t stolen and was properly declared upon entering the U.S.,” she stated to the Associated Press.

Paleontologist Paul Sereno, who has spent years uncovering dinosaur fossils in Niger’s Sahara, is advocating for the return of the nation’s cultural and natural heritage, including meteorites.

“When laws clearly state that rare minerals like meteorites are cultural artifacts, unique and valuable items cannot just be claimed without consideration for the country,” he told the AP.

“We are no longer in a colonial era,” he added.

In certain countries, including Morocco, a major source of meteoritic specimens for international markets, if an object is found on their territory, compensation is required. Nonetheless, due to the expansive desert regions and the informal trading networks, enforcement remains challenging.