The main mass of the Brenham meteorite could smash the world auction record.
The lot is valued at £500,000-800,000 ($717,500-1.1m) ahead of an April 20 sale at Christie's in London.
The meteorite record stands at $330,000, set for a fragment of Moon rock at Heritage Auctions in 2012.
"Main mass" refers to the largest intact fragment of a meteorite.
This example fell to Earth in Kansas around 1,000 years ago and is believed to be documented in local Native American glyphs.
Weighing in at 650kg, the lot is the world's largest intact pallasite - meaning it's formed of both iron and the precious stone olivine.
It also displays an attractive parabola shaped-dome, formed when it was hurtling through Earth's atmosphere.
Such oriented meteorites, which retain evidence of their fiery descent, are extremely rare.
They reportedly inspired the shape of NASA's Lunar capsules, due to their ability to remain stable and deflect heat.
Christie's comments: "This meteorite has been on exhibition since its recovery.
"An incomparably magnificent showpiece, the discovery of this mass was reported by hundreds of publications and is the finest meteorite of its kind in the world."
Meteorites recovered from documented falls have the greatest allure to collectors.
The main mass of the Zagami meteorite, which landed in Nigeria (narrowly missing a farmer) in 1962, is valued at £250,000-450,000 ($355,568-640,023).
Expert Robert Haag acquired it in 1988.
He identifies it as having been chipped from the planet Mars by an asteroid strike around 3m years ago.
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