to Do If You Think That You’ve
I’m sorry, but you have not found a meteorite. Yes, your rock is funny-looking and different from other rocks in the area where you found it, but it doesn’t have a fusion crust or regmaglypts, so why do you think it’s a meteorite at all? Your rock has a rough exterior, unlike the smooth appearance of most stony meteorites. It’s got vesicles (holes), which don’t occur in meteorites. Your rock is loaded with quartz or calcite, minerals that don’t occur in rocks from other bodies in the Solar System. The density isn’t right for a meteorite. On the basis of my experience with the various meteorwrongs that I’ve examined, you probably have a hematite concretion or some kind of industrial by-product (slag). I have heard many wonderful stories from people who swear that they saw the rock fall, that the rock wasn’t in their driveway yesterday, or that it split their tree in two. I can’t explain how your rock got to be where you found it, but I can say that it is not a meteorite. [Every rock that someone has described as “it wasn’t there yesterday” was just the right size for throwing. Really.] Not everything that falls from the sky is a meteorite.
Even if it is a meteorite, it’s not from the Moon or Mars. As I note on my Lunar Meteorites web page, meteorites are rare, lunar meteorites are very rare. Less that 1800 meteorites have been found in the United States in the past 200 years. Less than 1 in 1000 of all known meteorites are from the Moon, and the number is about the same for Mars. No lunar meteorite has yet to be found in the temperate environment of North America or Europe; all were found in deserts of drier continents. You’ve got a better chance of winning big in the lottery than finding a lunar meteorite. You say that your rock attracts a magnet or a compass. That’s nice. Most (>95%) of meteorites (irons and ordinary chondrites) attract cheap magnets because they contain iron-nickel metal. However, lunar and martian meteorites contain little or no metal, so they’re not magnetic. (Also, some terrestrial rocks contain magnetite, which is magnetic.) Don’t tell me that your rock “looks like” one of the photos of a lunar meteorite on my web site. Many kinds of terrestrial rocks “look like” lunar meteorites. Finally, I don’t want to hear, “Maybe this is a kind of meteorite nobody’s ever seen before.” Get real.
Think of it this
way. If it’s driving down the highway and it has 4 tires, 2 headlights, and
a trunk, then it’s probably an automobile, not an alien spacecraft.
Despite my rude admonishments, you still want to know if your rock is a meteorite and I feel some obligation to respond to your interest. Also, there is a chance that your suspicions are correct and that you have actually found some kind of meteorite. So, here’s what you should do.
Look at this information about meteorite statistics. Go through the Self-Test Check-List. If you’re still confused, try my Some Meteorite Realities website where many of the same points are stated in a different way. Look at the photos.
I urge you to saw your rock in two or cut and "end" off with a tile saw. (Or, bring it to a local rock shop where they are likely to have a rock saw. ) Most stony meteorites are ordinary chondrites. Metal grains are easily visible on the sawn face of an ordinary chondrite.
If you contact me, please use e-mail or send me a letter. Do not call me on the telephone. I do not answer or respond to telephone calls about meteorites. Why? I can’t identify meteorites over the telephone. (Nobody can.) Also, I don’t hear well and often don’t understand people who call me on the phone. So, e-mail me.
Please include a few good digital photos with your e-mail. If the photos aren’t in focus, they are of no use to me. (I seen few decent rock photos taken with a cell phone.) Include some object like a hand, coin, or ruler in the photographs for scale. Otherwise, send the rock or a piece of the rock to me. I will take a serious look at any rock that you send, as long as you don’t send lots of rocks and you provide the information requested above. Send the rock to:
Dr. Randy Korotev
UPS., FedEx, etc:
Dr. Randy Korotev
I’d rather have the whole rock, but I only need a piece at least the size of a golf ball to examine. Unless your rock is very beautiful, you will not be decreasing its monetary value by breaking off a small piece. As one meteorite dealer told me, “Every time I saw or break a meteorite in two I’ve increased its value.” Be sure to send me your return postal address, e-mail address, and the cost of return postage if you want your sample back. I will not save rock samples for more than a few months after examining them.
If you do send more than one rock, please give each of them names or numbers so that I can distinguish them when I communicate with you about them. I will not respond to letter requests that contain only photographs, requests that are made by telephone, or any request that does not include your name and information about where the rock was found (country or state).
If you are particularly certain that your rock is a meteorite and you really want to convince me (or any other scientist), then I urge you to obtain a chemical analysis at a commercial rock-testing laboratory. I recommend Actlabs. Ask for analysis code 4Litho. Please contact me first before sending a sample to Actlabs. I have no financial interest in Actlabs, I just know they do a good job.
Read what they have to say
submittal and sample
preparation. Unless you send a finely powdered sample, there will be an
additional charge for crushing and pulverizing (code RX5 or RX6). Actlabs
requests a 5-gram sample (a US nickel weighs 5 grams). However, they can do
the analysis on as little as 1 gram if you request “no LOI” (loss on
ignition, i.e., % weight loss when the sample is heated to a high
temperature). LOI is sometimes useful, but never critical, for determining
whether or not a rock is a meteorite.
Check your own data with "Chemical Composition of Meteorites"
If you have found a chunk of metal that you think might be an iron meteorite, you need to have it analyzed (at a minimum) for iron (Fe), nickel (Ni), chromium (Cr), and manganese (Mn). Unfortunately, I do not know a lab that does this cheaply. If somebody out there does, let me know.
October 5, 2015: I have received results of analyses of
370 samples from Actlabs and more than 100 samples from other labs. Only two of the rocks were meteorites,
both ordinary chondrites. The first
was found by a soldier in the Sahara desert, the other was also from the
Sahara and bought by someone who wanted to know if it was “real.” (I didn’t know the circumstances until
after he’d sent me the results. I was hoping that he’d found it.) So, once
again, finding a real meteorite is highly improbable.
Although I urge you to bring your rock to a local college or university and show it to a geologist or planetary scientist, very few scientists at universities have ever actually seen a lunar or martian meteorite. Even those who study lunar or martian meteorites have usually only seen photos or very small chips. A lunar or martian meteorite that is found in a temperate climate will be weathered and look very much like an unspectacular terrestrial rock (see Los Angeles). There are no simple or cheap tests that will allow anyone to honestly and confidently say “This is a lunar meteorite” or “This is a martian meteorite.” All such tests are time consuming and expensive.
Don’t call me on the telephone. I can’t identify meteorites over the phone. Don’t send me long e-mail messages. I won’t read them. I’ve been sent maps, movie files, videotapes, and CD’s and ZIP files full of photos of the find location and the tree that got struck. I didn’t look at them. I’m sure that there’s a really good story that goes along with your rock. I’ve heard it already. (OK, that’s not really true. Some people have sent me some really good stories that I will treasure forever.) I’m mainly interested in the characteristics of the rock, not the circumstances of how you found it. The rock speaks for itself. I do want to know, however, why you think it’s a meteorite. Don’t send me your whole rock collection or photos of your whole rock collection. Don’t send me long descriptions of the rock. That doesn’t help. (In one of my other lives I’m a birder, which is the what nonbirders call a birdwatcher. Birders have this saying, “The hardest bird to identify is one a nonbirder describes to you.”) Don't ask me to buy your rock. Don't ask me how much is it worth ($). I don't know.
If you send me a rock, I’ll look at the rock and maybe show it to my friends. I might measure the specific gravity, if you send me at least 10 grams. Some terrestrial rocks can instantly be recognized as not being meteorites. For example, no stony meteorite has a specific gravity greater than 4. I might do a streak test. I might do a scratch test. No meteorite has layered features or swirls, yet many terrestrial sedimentary rocks are layered. (Layering occurs because the rocks formed at the bottom of an ocean or a sea. There are no seas on asteroids, Mars, or the Moon.) If there is nothing about the rock that suggests to me that it is a meteorite, then I will not continue with further tests. It’s my call.
If you follow my advice about Actlabs, I’ll make a serious study of the analytical report and and send you a serious opinion about what it means.
Like your family doctor, I admit that I might be wrong, particularly if I only do a quick visual assessment. You may really have a meteorite and I may think that it is not. You are always entitled to a second opinion. Rocks that are basalts (solidified volcanic lava) and related volcanic rocks are common on Earth, Moon, Mars, and occur among the meteorites from asteroids. All of the tests that identify a basalt as being a meteorite and not from Earth are time consuming and expensive. If your basalt doesn’t have a fusion crust, I am not going to want to spend the time and effort it would take to prove that it is or is not a meteorite.
I will acknowledge that I have received your rock (send me your e-mail address). Please note that I may not have an answer for you for several weeks. Your tax dollars pay me to do a variety of things that NASA wants done, so I only deal with potential meteorites occasionally. Be patient.
Finally, be advised that I reserve the right to post photos of your rock - ones you provided me or ones that I take myself. No names are used. The goal here is education, not ridicule.
I will not pursue the mineralogical or chemical tests necessary to prove that a rock is a meteorite unless I believe that there is a good chance that the rock is a meteorite. I have discontinued the service of analyzing for a fee any rock that you send; send it to someone else for analysis (see above). I won’t respond to e-mail messages that make little attempt to provide the information I request above in the "What You Should Do"
It is impossible to conclusively identify a meteorite from a photograph. Many Earth rocks look like some meteorites. Some meteorites look a lot like Earth rocks.
The rock on the left is the
If I conclude that your rock is a meteorite, I will urge you, with my help, to follow the procedure for legitimizing meteorites and making them “official,” as described at this web site:
Please note that “20% of the total mass or 20 g, whichever is less, must be deposited in a museum or other institutional collection that routinely makes material available for scholarly research. Meteorites lacking type specimens will NOT be approved by the Nomenclature Committee.”
If your meteorite is not “approved by the Nomenclature Committee,” then it will provide little or no monetary value to you. I will not provide you with a "Certificate of Authenticity" or the equivalent. I know some meteorite dealers if you are interested in selling your meteorite. However, nearly all meteorites are ordinary chondrites, which do not have a high commercial value unless they are spectacularly attractive or are of special interest, like the Park Forest meteorite (an L5 chondrite, which is common) that fell in Chicago in 2003 (samples are being sold by dealers for $35-50/gram; dealers will pay less to you).
I and my colleagues will want to do a thorough characterization of the meteorite. Such a characterization may involve colleagues at other institutions. We will then want to publish the results in a scientific journal. The more publicity and exposure that your meteorite gets in the scientific literature, the more valuable it will be. Also, the more papers I publish, the sooner I can retire and search for meteorites. Be aware, however, that most meteorites are not special and may not get more than a paragraph in The Meteoritical Bulletin.
Finally, if you should find a large, attractive meteorite, I’ll probably urge you loan it to Washington University so that we can put it in our museum. We’ll put it right next to the tag saying "On loan from <your name here>."
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