A lunar meteorite is a piece of the Moon. In the purest sense of the word, it is a "Moon Rock". But, when most people hear the phrase "Moon Rock", they automatically think of rock samples brought back from the Moon by the Apollo astronauts. This is why many people think that owning a Moon Rock is illegal - because the Apollo samples are illegal to own by private citizens. Apollo Moon Rocks are NASA and US government property which cannot be sold or exchanged to private citizens.
Lunar meteorites are "Moon Rocks" just the same as the Apollo samples, except for one major detail : lunar meteorites were delivered to Earth by Mother Nature, and not astronauts who are government employees.
Lunar meteorites are found on Earth because they were ejected from the surface of the Moon by violent asteroid impacts. Asteroids slam into the lunar landscape, and the resulting impact hurls great amounts of lunar rocks out of the Moon's weak gravity well and into space. Eventually, some of these ejected Moon Rocks stray too close to Earth's gravity and are captured.
Once a space-borne Moon Rock is pulled in by Earth's gravity, it begins a fiery plunge through the atmosphere that ends with an impact somewhere on Earth. Most of these falling meteorites are lost in the Earth's oceans, but some fall on land where they can be found and recovered.
The Saharan Desert is a perfect landing spot for these meteorites. It is vast, desolate, dry, and unpopulated. Meteorites that fall in the Sahara are preserved for long periods of time by the arid conditions - increasing their chances that they will eventually be found. Once these meteorites are found, they are taken to a lab and analyzed to identify their composition. Once they are confirmed to be of lunar-origin, they are sometimes made available for purchase to the public.
Purchasing lunar meteorite by private citizens is legal because the countries of origin for most of the meteorites (Morocco and Mauritania) have no legal restrictions on the trade of meteorites. It is a classic case of "finders keepers".
Now, the obvious question is : why purchase a lunar meteorite? Well, for some people the answer is simple. It is an awe-inspiring thing to touch and hold. It is literally a piece of an alien world beyond the Earth. It is a tangible piece of our nearest celestial neighbor that has enchanted the imaginations of our ancestors for millennia. It is a rock that was formed before mankind ever walked the Earth. Holding a lunar meteorite is closest thing most human beings will ever get to walking on the Moon.
Speaking of which, there are some silly but cool things you can do with a lunar meteorite. First, you can place it on the ground and stand on it - thereby joining the exclusive club of astronauts who have "walked on the Moon". Yes, it's not the same as actually travelling to the Moon, but it's much cheaper and safer than strapping yourself into a rocket ship. Secondly, you can break off a tiny piece and eat it. Why? Because you then join the exclusive club of people who have a piece of the Moon inside their body. Heck, how many people can say they have eaten a piece of another planet?
I know, that second example is downright silly, and I don't seriously recommend eating rocks - it's bad for your teeth and your spouse will question your sanity (and maybe revoke your credit card access). But I would be a liar if I said I didn't immediately want to consume a piece of the Moon as soon as I could - and I did. Call me nuts, but I have a piece of the Moon incorporated into my body and that makes me cool in my book (and bat-guano crazy in my wife's book).
On a more serious note, there are some logical reasons to own a lunar meteorite. First, it's a great educational and outreach tool. Students of geology and planetary sciences can benefit directly from studying these Moon Rocks. Children are especially enchanted by a piece of the Moon - it sparks the imagination and hopefully plants a seed of curiosity and wonder that will result in that child growing up to take an interest in the sciences. Lunar meteorites can teach us much about the chemistry and history of our Moon, our Earth, and the solar system.
Now is a great time to invest in Moon Rocks because it is a buyer's market. Up until recently, lunar meteorites routinely sold for upwards to $1000 per gram. But thanks to recent recoveries in the Sahara, large quantities (relatively speaking) of lunar meteorites have been recovered This has resulted in sizeable injection of material onto the market which has depressed prices to historic lows. You can now own a tiny piece of the Moon for less than the price of a fast food meal, or you can own a larger piece for less than you would expect to pay for a ticket to a baseball game. Yes, it is not only possible to own a piece of the Moon, but now it is affordable for most collectors on almost any budget.
So, where does one buy a Moon Rock and be assured that you are actually getting a lunar meteorite and not a piece of driveway gravel? Well, you buy one from an established meteorite dealer with a good reputation - like your's truly who wrote this. Don't just go to eBay or Google and jump on the first offering you see. Do a little homework first. Who is this person selling the meteorites? How long have they been in business? What is their reputation amongst the community of collectors and dealers? These are all valid questions that should be answered before coughing up your hard-earned money for a Moon Rock.
And we have reached the end of lunar journey. But, what about Martian meteorites? Yes, you can also own pieces of the planet Mars or asteroid Vesta thanks to Martian and Vestan meteorites, but that is another story for another time....