No hyperbole is necessary here, nor breathless embellishment.

This lot in Heritage Auctions’ August 7 Nature & Science event is nothing less than as advertised: “a large piece of the moon.”

To be precise, 6.4 pounds large. That is a staggering size for a moon meteorite, considering there are but a few hundred pounds of lunar material known to have crash-landed on our planet.

And that is what this is: a 7.5-inch piece of the moon sliced off the lunar surface by a passing asteroid that eventually made its way to the desert of Morocco, where it was discovered and first sold – from a dealer to a collector-curator – only six years ago. It bears the classification NWA 8641 because it’s the 8,641st meteorite discovered in northwest Africa.

The Meteoritical Bulletin reveals plenty about its petrography, its geochemistry, its physical characteristics. The literature explains, dryly, what the eye can plainly see: This is “a large rounded, ellipsoidal dark gray stone with white clasts visible and with a beige, clayey coating on one side.”

But academia misses the most obvious lure.

“The moon is the only extraterrestrial body any human has ever touched,” said Craig Kissick, Heritage Auctions’ Director of Nature & Science. “It’s the satellite of our planet. It doesn’t get more human than that. And, without question, this is one of the finest large lunar meteorites that can be privately owned.”

That one can even purchase such a thing, 51 years after Neil Armstrong, Buzz Aldrin and Michael Collins first landed Apollo 11 on the moon’s surface, seems almost unfathomable. After all, fewer than 0.5% of all meteors found are lunar in origin; The Meteoritical Bulletin reports there only some 200 meteorites classified as lunar in origin, and those moon meteors that are discovered are usually diminutive – the size of small rocks.

The Apollo astronauts, of course, were not allowed to keep those samples returned to Earth. All of those are the property of the United States government, and reside with NASA or the Smithsonian Institution’s National Air and Space Museum.

“The truth is, this is a museum-quality specimen, period,” Kissick said of the lot being offered August 7. “We use that phrase a lot. We tend to throw it around – ‘museum-quality.’ But the truth is, this is a piece that would appeal to the most sophisticated collector or institution. It’s so classic-looking: the outer part looks like the surface of the moon, and the interior allows you to see the composition of the moon. This really is one of those Holy Grail pieces.”

The upcoming Nature & Science auction is not wanting for significant space artifacts – including several associated with the Apollo astronauts.

There’s also a 5.14-pound Martian meteorite also discovered in northwest Africa. Like its lunar counterpart, this slice of Mars is one of the largest examples of its kind discovered – and, now, brought to market.

The Meteoritical Bulletin notes there are but 225 meteorites classified as Martian in origin; and they, too, are usually small. The one being offered by Heritage Auctions is sizable and significant.

“Quite simply, it’s a large, exquisite example of a rare meteorite that just doesn’t come in big sizes like that,” Kissick said. “There is a finite amount of this material around – of the moon, of Mars. Can you imagine owning it? How amazing. How cool.”

Click here to browse all the items in the August 7 Nature & Science event and view high-resolution photos.