A dispute over the world's most expensive meteorite. It may have been auctioned illegally.

The largest piece of Mars ever found on Earth sold in New York for $4.3 million. The auction at Sotheby's ended with applause, but in Niger—the origin of the space rock—questions about the legality of its export were raised instead.

In early June, a record was set at Sotheby's New York auction house . A 24.7-kilogram (55-pound) rock from Mars, the largest piece of the Red Planet ever found on Earth, sold for $4.3 million . Both the buyer and seller remained anonymous. While collectors were amazed, the Niger government began asking uncomfortable questions. How did their cosmic treasure end up at auction, and who was behind it? Now, they're announcing an investigation.

Meteorites have captured the human imagination for centuries. Once revered as divine gifts, they now find their way into private collections, museums, and research laboratories. On the collectors' market, they resemble works of art. And quite expensive, too. The most valuable specimens are from the Moon and Mars . A high-quality fragment of the Red Planet can cost from tens to hundreds of thousands of dollars per kilogram.

Although meteorites can fall anywhere on Earth, the Sahara is a veritable goldmine for meteorite hunters. The dry air and lack of vegetation favor their preservation, and the vast desert landscapes facilitate the search. In Morocco , Niger , and Mauritania , entire networks of "meteorite hunters" operate, often selling their finds to international dealers.

However, this system is rife with legal gray areas. Many countries, including Niger , lack clear regulations regarding the trade in meteorites. As a result, treasures from the desert can cross borders almost unnoticed.

The story of the NWA 16788 meteorite began in November 2023, when it was found in a region in Niger, just 90 km from the Chirfa oasis. According to Italian sources, the local community sold it to a middleman, who then transferred the "jewel" to a private gallery in Arezzo. There, it underwent extensive research, and its fragments were subsequently exhibited in Italy.

The rest of the meteorite – the largest and most spectacular one – ended up in the Sotheby's catalogue under mysterious circumstances.

The auction ended with a record sale of $1 million, but the Niger government quickly expressed doubts about the legality of the export of the treasure and announced an investigation.

Professor Paul Sereno of the University of Chicago, who has been studying Saharan fossils for years, believes that the meteorite's export violated Niger's national heritage protection laws . Although the law lacks the word " meteorite ," the object could fall under the category of "mineralogical specimens," which are already protected.

The dispute over NWA 16788 is part of a broader discussion about whether space rocks are solely collectors' items or a common good that should remain in their country of origin.