# Reality Examples Examples

0 Most rocks are not meteorites… …so your rock is probably from Earth. Think of it this way: If you see it driving down the freeway and it has 4 wheels, 2 headlights, and a trunk, it’s probably an automobile, not an alien spacecraft.

1 The chance of finding a meteorite is exceedingly small. see numbers for the U.S. Even experienced meteorite hunters can go for years between finds.

2 The chance of finding a lunar or martian meteorite is even smaller. Only about 1 in 1000 meteorites is from the Moon or Mars. I’ve been looking for one for 40 years and I haven’t found one.

3 The chance of finding a meteorite that has just fallen is even smaller. search The Meteoritical Society database Since 1900, the numbers of recognized meteorite “falls” is about 690 for the whole Earth. That’s 6.3 per year. Only 98 of those occurred in the US. That’s less than 1 per year. Even when a meteorite is observed to fall, experienced meteorite hunters may find only a few stones when hunting dawn to dusk for a week.

4 Not every rock that falls from the sky is a meteorite. thud Most rocks that fall from the sky are not meteorites.

5 Not every rock that “looks like” a meteorite is a meteorite. looks like It is often not possible to determine whether a rock is a meteorite just from its appearance. In particular, achondrites such as meteorites from Moon and Mars look very much like some types of common Earth rocks. Also, many people have told me that their rock “looks just like” some meteorite in a photo they saw. Sorry. It doesn’t work that way. They don’t know what to look for.

6 Some meteorites don’t look like meteorites. Kalahari 009 If someone had walked into my office with this rock, I’d have said that it wasn’t a meteorite.

7A If it does not have a fusion crust, then it’s probably not a meteorite. fusion crust

more photos Some meteorites do not have obvious fusion crusts, but that’s rare. Usually there’s fusion crust on at least one face.

7B “Maybe the fusion crust got worn off.” no fusion crust If she’s wearing a pretty dress and playing a grand piano on a stage with a symphony orchestra behind her, then she’s probably a concert pianist. If she’s jogging down the beach with her dog, then she might be a concert pianist, but probably not. How can you tell?

8 If it has some kind of rind or coating, the rind or coating is probably not a fusion crust and the rock isn’t a meteorite. rinds & coatings There are numerous processes on Earth, such as chemical weathering, that cause rocks to have coatings and rinds. Some of these, particularly desert varnish, can look remarkably like a meteorite fusion crust.

9 If it’s got a thick rind or coating, then it’s not a meteorite. too thick Fusion crusts are thin because as soon as the exterior of the meteorite melts, the liquid is sloughed off because of the high velocity of travel of the meteoroid through the atmosphere. Fusion crust doesn’t build up, except perhaps on the trailing side.

10 If the inside is the same color and shade as the outside, then it’s probably not a meteorite. fusion crust Fusion crusts are usually darker than the interior of a meteorite.

11 If it “looks burned,” it’s probably not a meteorite. burnt meteorite Meteorites don’t burn. Meteorites are not burned. The outside has melted, but they haven’t burned and they don’t “look burned.”

12 If it’s a big rock, then it’s probably not a meteorite. too big Most stony meteorites are smaller than people think they are. If you like statistics, see this. Also, see this for the masses of the >70 individual stones that have been found from the recent fall of the Sutter’s Mill meteorite in California. Iron meteorites can be big, however: Willamette | XinJiang | Campo del Cielo | Hoba

13A If it’s big and it does not have regmaglypts, then it’s probably not a meteorite. regmaglypts Not all meteorites have regmaglypts, however the big ones usually do.

13B If it has dimples or pits, they’re not necessarily regmaglypts. not regmaglypts Not all dimples are regmaglypts. The dimples in many of these photos are deeper for regmaglypts.

13C If it has “craters” on the surface, they’re not craters and the rock is not a meteorite. asteroids and meteoroids Asteroids have craters, meteorite do not. The surface material ablates away as the meteorite comes through the atmosphere. See next.

14 If it’s angular, with sharp edges or points and no smooth sides, then it’s probably not a meteorite. angles and edges For small meteoroids, 90% of the mass is lost to ablation as it comes through the atmosphere. Edges, “corners,” and any other protuberances are the first parts to ablate away. Put an ice cube in water and wait for 90% to melt. The “cube” that’s left will have no edges or points. It’s like that with meteorites.

15 If it’s stony (not an iron) and has a rough exterior, then it’s probably not a meteorite. too rough

16 If it’s stony (not iron) and has protuberances, then it’s probably not a meteorite. protuberances 1

protuberances 2

17A If it’s square, rectangular, or has flat sides or parallel sides, then it’s probably not a meteorite. flat 1 | flat 2

rectangular As above, flat sides and square corners are not consistent with an object that has come through the atmosphere.

17B If it’s highly oblate (flat and thin), then it’s not a meteorite. oblate Except for Frisbees and flying saucers, oblate objects are not all that aerodynamically stable and would be break apart during the descent through the atmosphere.

17C If it looks like a vegetable, it’s not a meteorite. potato rock What more can I say.

18 If it has swirls, foliation, radiating features, concentric features, or tubes, then it’s not a meteorite. swirls | foliation | radiate 1 | radiate 2 | concentric Although there may be processes in space that can lead to such rocks, we haven’t seen meteorites like this yet.

19 If it’s got layers, laminations, or any kind of planar or parallel linear features, then it’s definitely not a meteorite. layers 1 | layers 2 Layered rocks occur on Earth because the Earth has gravity. Most meteorites come from objects (asteroids) too small to have any appreciable gravity. If there is no gravity, then there is no way to form layers. Here is the only exception I know about, and it’s a terrestrial weathering effect.

20 If it’s got veins, particularly ones that stick out or appear to be planar, then it’s not a meteorite. veins 1 | veins 2 Melt veins are seen in some meteorites, but they are never linear. Rarely, there might be veins of impact melt (see NWA 482 and Harper Dry Lake 036). Some ors have veins of metal. Most of the veins in these photos, however, are fractures that have filled with quartz. Quartz-filled fractures are common in Earth rocks but are not seen in meteorites.

21 If it’s got fractures or filled fractures, then it’s probably not a meteorite. fractures If a meteoroid is fractured, then it will break apart along the fractures as it passes through the atmosphere. Ordinary chondrites that have been on or in the Earth a long time, will self fracture as they metal rusts, but they will look rusty and not like the rocks in the photos. (See story and photo of the Lake House chondrite, for example.)

22A If it contains elongated minerals or clasts, then it’s probably not a meteorite. needles It is rare for the aspect ratio of a clast or large mineral in a meteorite to exceed 3-to-1.

22B If it has clasts or minerals grains with square, rectangular, or parallelogram shapes, then it’s probably not a meteorite. geometric Geometric shapes happen in terrestrial rocks, but the minerals that cause this are rare in meteorites.

23 If it’s spherical or circular, then it’s probably not a meteorite. spheres 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 There are processes on Earth that lead to spherical rocks (spheroidal weathering, tumbling and abrasion in water). These processes don’t occur where most meteorites come from. Here is a photo of the only exception of which I’m aware: Canyon Diablo spherules

24A If it contains round things, the round things are not necessarily chondrules. round things 1

round things 2 Lots of Earth rocks contain round things.

24B If it looks like one of the breccias on my lunar meteorites site, it’s not necessarily a meteorite or a Moon rock. breccias 1

breccias 2

breccias 3 There are a number of geologic processes on Earth that lead to rocks that resemble impact breccias. Most of the rocks in these images are pyroclastic (volcaniclastic) rocks.

25 If it’s got lots of holes in it, then it’s not a meteorite. vesicles & amygdules

more vesicles 1

more vesicles 2 Very few stony meteorites have vesicles or holes. In those that do, the holes are sparse and small. Vesicles require gas and that the rock was once molten. Most meteorites were never molten. Iron meteorites sometimes have holes, however.

27 If it contains lots of amygdules, then it’s probably not a meteorite. vesicles & amygdules

more amygdules Some hot-desert meteorites have terrestrial material filling rare vesicles.

28 If rock or mineral grains stand out from the matrix or have been plucked out leaving a cavity, then it’s probably not a meteorite. outies & innies In many terrestrial sedimentary rocks, the clasts are often harder than the matrix. Sometimes they pop out of the rock. That doesn’t happen much in meteorites.

29 If it’s long and thin, it’s not a meteorite long-thin 1

long-thin 2

long-thin 3 A rock or piece of metal with a high aspect ratio (length-to-width) is not aerodynamically stable and would break apart in the atmosphere.

30 If it contains quartz, then it’s not a meteorite. quartz Quartz is the only common mineral that will easily scratch glass. Try to scratch glass with a sharp edge of the rock. If it makes a deep scratch, it’s not a meteorite.

31 If it consists of hematite or magnetite, then it’s not a meteorite. concretions Iron-oxide nodules or concretions are the most common kind of meteorwrong sent to us. Highly weathered meteorites may contain some hematite, magnetite, and maghemite. Do a streak test.

33A If the rock does not rather strongly attract a cheap magnet, then it is probably not a meteorite. magnetic attraction metal, iron, & nickel Don’t use a rare-earth (neodymium) magnet to test for magnetic attraction. A meteorite will attract a cheap refrigerator (ceramic) magnet or compass.

33B If the rock attracts a cheap magnet but you cannot see shiny metal grains on a sawn or broken surface, then it’s not a meteorite. Meteorites attract magnets because they contain iron-nickel metal. Earth rocks don’t contain iron-nickel metal. Many Earth rocks attract magnets, however, because they contain the mineral magnetite.

33C If the rock contains shiny things that look like metal, but the rock does not attract a magnet, then the shiny things are probably not metal and the rocks is not a meteorite. Some sulfide and oxide minerals look like metal. Micas are often shiny.

33D If it looks like metal but does not strongly attract a cheap magnet, it’s not a meteorite. We’ve been sent chunks of silicon, ferromanganese, chromium, and other industrial metals.

33E If it does not attract a cheap magnet, then it could still be a meteorite, but it is probably not. Many of the rarest types of meteorites (achondrites) do not attract a magnet, but most Earth rocks also do not attract magnets.

34A If it is made of metal or looks metallic, then it might be a meteorite, but it’s probably not. metal 1 | metal 2

metal 3 Humans have been making and losing metal things for hundreds of years. Some minerals look metallic but are not.

34B If it looks metallic and is shiny on the outside, it is not a meteorite. shiny 1 | shiny 2

shiny 3 Some sulfide minerals look metallic and some non-ferrous metals are shiny.

35A If it is “heavy for its size,” then it might be a meteorite, but it’s probably not. density & specific gravity The commonest kind of meteorites, the ordinary chondrites, contain iron-nickel metal; that makes them denser than most Earth rocks. However, some Earth rocks are dense like meteorites. To confuse the issue, some rare meteorites (achondrites) have low densities like common Earth rocks.

35B If it’s not heavy for it’s size, then it might be meteorite, but it’s probably not.

36 If it’s reddish, particularly on the inside, then it’s probably not a meteorite. too red

too colorful Most meteorites are shades of grays and browns; some may be reddish on the outside.

37 If it shows polygonal or columnar jointing, then it’s not a meteorite. jointing Although jointing has been observed volcanic rocks on Mars, we haven’t yet seen a meteorite with contraction fractures. Any meteorite would break along such fractures when the meteorite hits Earth’s atmosphere.

40 If it does not look like other rocks in the vicinity, then it might be a meteorite, but it’s probably not. unlike Glaciers and flooding have dropped a lot of unusual rocks far from where they came from.

41 If you found it on the beach, then it’s not a meteorite. beach I am aware of only one meteorite, Southampton (pallasite), that was found on a beach. If a stony meteorite landed in the water and later washed up on a beach it would have lost its fusion crust as a result of abrasion by wave action. If it were an ordinary chondrite, it would likely have broken apart from rusting of the iron metal. If it survived as a rock, it would be all but impossible to identify as a meteorite just “by looking.” It would not look at all special, except maybe for some rusty spots. But, who knows? Nobody has ever found and recognized one!

42 If you found it in a stream bed, along a river, or any other place where there are lots of rocks, then it’s probably not a meteorite. stream Successful meteorite hunters search for meteorites in places where there are not a lot of rocks. If you want to find your car easily, park it in an empty parking lot. There’s one important exception: Some meteorites have been found in deserts that have desert pavement.

43 If you found it near a road or railroad track, then it’s not a meteorite. railroad It may have fallen off a train or truck.

44A If the rock is “really hard,” then it’s probably not a meteorite. quartz Because meteorites don’t contain quartz (the hardest common terrestrial mineral), they’re not all that hard.

44B If it looks metallic and you can bend it or break it, then it’s not a meteorite. Iron meteorites don’t break, unless they’re badly rusted.

45 If it’s in a conspicuous place, then it’s not a meteorite. conspicuous 1

conspicuous 2

conspicuous 3 Unless it’s in a museum

46 If you found a lot of them in one place, then they are not a meteorites. too many 1

too many 2

too many 3 Meteorites break apart in the atmosphere 10 miles or more above the Earth’s surface. The fragments are spread out over miles (strewn field). The chances that 2 or more land within seeing distance are very small.

47 If you found it in a crater, then it’s not a meteorite. not a crater 1 | not a crater 2 | not a crater 3 Meteorites hit the ground at terminal velocity, about 200-400 miles per hour. That’s not fast enough to make a crater unless the rock is large (>meter size? I really don’t know).

48A If you saw a meteor and then found a stone, then the stone is not a meteorite. meteor Read this.

48B If you found a rock, it might be a meteorite, but it is definitely not a meteor. You can not hold a meteor in your hand. A meteor (“shooting star”) is the visible streak of light in the sky from a meteoroid or micrometeoroid entering the Earth’s atmosphere. The meteoroid compresses the air which causes the exterior to heat and glow (incandesce). The meteoroid sheds glowing material in its wake, causing the streak in the sky.

49 If you found a rock that was hot to touch or appears to have been subjected to “extreme heat,” then it’s not a meteorite. hot rock 1 hot rock 2 Few meteorites have been collected immediately after they fell, and reports vary from “hot” to “cold.” The physics of the process, however, lead scientists to favor “cold” to perhaps a bit warm for the smallest meteorites. Outer space is exceedingly cold. A meteoroid in space is very cold. It only takes seconds for a meteorite to pass through the atmosphere. Although the exterior gets hot enough to melt, the hot material immediately ablates away, so conduction of heat to the inside of the rock is inhibited. Also, rocks are not good conductors of heat. Meteorites don’t start fires. The interior of a meteorites shows no evidence of having been heated during the atmospheric entry process.

50 If it’s been in your family for years, it’s probably not a meteorite. Grandpa’s old rock But then…

51 If your metal detector says the rock contains nickel, then it’s lying. no metal detectors Metal detectors aren’t that smart. They might be able to tell nickels from pennies, but they can’t tell if iron metal contains enough nickel metal to be a meteorite.

52 If it’s radioactive, then it’s not a meteorite. radioactive Most meteorites are less radioactive than are most Earth rocks. The only meteorite of which I am aware to actually register on a Geiger counter is lunar meteorite Sayh al Uhaymir 169, which has 600-700 times the abundances of thorium and uranium than an ordinary chondrite.

53 If there’s writing or a picture on it, then it’s not a meteorite. picture

54 If it contains fossils, then it’s not a meteorite. fossils

55 If it has a face, then it’s not a meteorite. face Yes, these photos were sent to me by someone.

56 Many-to-most rocks sold over the Internet as meteorites really are meteorites; some are not. selling slag 1 There are many reputable meteorite dealers that sell real meteorites on the Internet. I have bought several meteorite specimens from such dealers. However, there are foolish or devious people who try to sell backyard rocks as meteorites. Most rocks offered on e-bay for prices >$10,000 are not really meteorites. Sometimes, cheap meteorwrongs are offered for sale, however.

selling slag 2 Since 2004 I have received thousands of e-mails and tens of thousands of photographs (really) from a disturbed man in Sweden who claims that the “rocks” in the photos are “ultra extreme amazing !!!” lunar meteorites. Here are a few of the photos. All the stuff in the photos is slag.

57 Advertisements for alleged meteorites that are filled with meaningless, pseudoscientific mumbo-jumbo and absurdly high prices are usually selling just rocks. caveat emptor Some people just don’t have enough real work to do.

58 If you find a real meteorite, it isn’t worth as much ($) as you think or wish. cheap There are several factors that affect the price of a meteorite: rarity of the type of meteorite, how big or small it is, intrinsic attractiveness, whether it’s a fall or a find, and whether there is a good story to go with it.

59 Meteorological is not the same as meteoritical. meteorological Both words involve atmospheric phenomenon.

60 I have seen nearly every lunar meteorite but I have never found one myself. I like to look for rocks when I’m walking. So, why do you think that you found one?

61A Nobody can identify a meteorite over the telephone. Don’t call me on the telephone. I won’t answer. I don’t hear well. I don’t want to know your story. There is nothing you can tell me over the telephone that allows me to say “Your rock is a meteorite.” I don’t want to know the circumstances about how you obtained it. I want to see the rock, a photo of the rock, or a chemical analysis of the rock. The rock speaks for itself, and rocks don’t speak on the telephone. E-mail me. Send photos. I might put your photo on this site.

61B I don’t want you to bring your rock(s) to my office. Send me photos. There’s no polite way to say this. Here’s what happens. (It’s happened many times.) You go to all the trouble of driving here, finding a place to park, and hauling your rock up to my 3rd floor office. I look at your rock and in 20 seconds I tell you that it’s not a meteorite for one or more of the reasons I present here. Then you ask, “Well, what is it?” I say “I don’t know” because I’m not a geologist. I’m just a retired geochemist who studies Moon rocks.” You want to stay and chat. You’re not going to change my opinion with any story you tell me. I need to get back to work.

62 I can’t positively identify a meteorite from a photo… …particularly if it was taken on a mobile phone. Some people, however, have sent me some really great photographs.

63 In English, there is only one way to spell meteorite. I have received e-mails with meteorite spelled many different ways: mÃ©tÃ©orite, mateorite, mateorito, meadorite, meatioright, meator, meatorite, medeiorite, medeorite, mederite, mederoite, mediroit, medorite, medrolite, meeorite, mentor, meorite, meoteorite, meotorite, mereorite, merteorite, met5eorite, mete, meteeor, meteiorrite, meteirite, météo, meteoiarte, meteoite, meteorait, meteorete, meteori, meteoric, meteorid, meteoride, meteorie, meteoriet, meteorilite, meteoriote, meteorit, météorite, meteorith, meteorito, meteoritote, meteoritre, meteoritt, meteoritte, meteoro, meteorolite, meteorprite, meteortie, meteory, meteoryt, meteotite, meteprite, meter, meteright, meteriod, meteriorite, meteriot, meteriote, meterite, metermortie, meteroide, meteroit, meteroite, meteror, meterorite, meterote, meteroyty, meterrite, meterrite, metetro, meteurite, metheorite, metior, metiorit metiorite, metoerite, metor, metoor, metorie, metorit, metorite, metortie, metoroite, metreot, metriote, métrite, metro, metroite, metrorite, metterrite, meturate, metworite, maturate, miderorite, miteorete, miteorite, moteor, motoit, mrtrorite, & mteorite

64A Suggested by Martin (an expert): “If an expert tells you that your rock is not meteorite, then: Believe him!” Or, seek the advice of another expert. But be aware – all meteorite experts I know are so deluged with questions by wannabe meteorite finders that many likely won’t reply. I get contacted about 16 times a day. So, I don’t have time to chat with you and I have no interest in arguing with you if you do not agree with my free opinions. I do this for free. If you don’t like my response, contact someone else.