The largest piece of Mars on Earth is being auctioned in New York: when will it be auctioned and what is the starting price?

The largest piece of Mars ever found on Earth will be auctioned in New York : weighing 24.67 kilograms, it will go on sale on July 16th for a starting price of $1.6 million . The piece was discovered on November 16th, 2023, by a meteorite hunter who found it in the Agadez region of Niger.

Sotheby's auction house estimates that the piece, abbreviated as NWA 16788, could fetch US$4 million due to its impressive size and rarity. Of the 77,000 meteorites recorded on Earth, only 400 come from Mars, weighing a total of about 374 kilograms.

“Weighing 24.67 kilograms, NWA 16788 represents approximately 6.5% of all currently known Martian material,” the company said in a statement released Tuesday.

The piece is 70% larger than the second-largest piece of Mars found on Earth. "It is covered with a reddish-brown fusion crust that gives it an unmistakable Martian hue ," the auction house explained.

Also observed regmaglyptus . These are small depressions caused by the intense heat during its entry into the Earth's atmosphere. According to experts, the meteorite shows little terrestrial weathering, suggesting that its physical and chemical properties have remained almost intact since its recent arrival in the Sahara Desert.

About 21.2% of NWA 16788's volume is composed of maskelynite , a type of glass that forms when an asteroid impacts the surface of Mars with such force that the intense heat and pressure transform the original mineral rock. That same impact would have thrown the fragment from the planet. Scientists estimate that of all the craters on that planet, only about 19 are large enough and have the energy required to produce this type of ejection.

NWA 16788 is classified as an olivine-microgabbroic shergottite, a variety of Martian meteorite formed by the slow cooling of magma. Scientists believe that analysis of this specimen could lead to an update to the classification system for these bodies.

Cassandra Hatton , Sotheby's vice president of science and natural history, said: “NWA 16788 is a discovery of extraordinary importance: the largest Martian meteorite ever found on Earth, and the most valuable of its kind ever offered at auction.”

“With its journey through space and time, its immense size, and its unmistakable red color distinguish it as a once-in-a-generation find. This remarkable meteorite provides a tangible connection to the red planet, our celestial neighbor that has long captured the human imagination,” he added.

The piece was cataloged and featured in the 113th issue of the Meteorical Bulletin (2025), the official publication dedicated to the scientific record of meteorites. Before arriving at the auction house, the Martian fragment was publicly displayed at the Italian Space Agency in Rome during the 2024 European Researchers' Night , and was also part of a show at a private gallery in Arezzo, Tuscany.