Several hundred meteorites found on Earth are lunar — knocked off the Moon by impacts and picked up centuries or millennia later, mostly in Antarctica and the Sahara.

They are identified by matching their chemistry to the Apollo and Luna samples, which is why the returned material is worth so much more than its weight: it is the reference standard. Between them the meteorites sample the whole Moon at random, including the far side, which no mission has ever brought back from — until Chang'e 6 in 2024.