Meteorite Identification: Pictures, Tests and Meteorwrongs

The properties that identify Meteorite (and Meteorwrongs) — streak: A genuine meteorite, when scratched on an unglazed porcelain plate, normally should not leave a streak; color: Mostly black or brown with a smooth surface (fresh fusion crust); the crust weathers to a rusty brown color over time. For a rock, texture and grain size matter more than any single hardness number.

• Magnet test: most meteorites contain metallic iron, so a magnet will often stick to them. Safety: The magnet test is not 100% reliable — stony meteorites can be only weakly magnetic, and many terrestrial rocks (magnetite, slag) are also magnetic, so this test alone is not conclusive.
• Fusion-crust test: stony meteorites typically have a thin crust on their surface, melted by friction as they passed through the atmosphere.
• Regmaglypts test: iron-nickel meteorites are rarely rounded — their surfaces often have irregular, fingerprint-like pits.
• Vesicle-exclusion test: meteorites should not contain vesicles (gas bubbles); terrestrial volcanic rocks and metallic slag often do.
• Quartz-exclusion test: meteorites do not contain the quartz common on Earth — if a sample clearly shows light-colored quartz crystals, it can generally be ruled out as a meteorite.

• Slag (an industrial smelting/iron-making byproduct): Slag often contains vesicles and has a burnt, melted appearance; it is often magnetic due to iron content, making it one of the most common sources of mistaken meteorite identification. Slag is commonly found near railroad ballast, road fill, and other signs of human activity.
• [Magnetite](/lookup/rocks-and-minerals/magnetite): A streak test distinguishes them: magnetite leaves a grayish-black streak, hematite leaves a reddish-brown streak, and a genuine meteorite normally leaves no streak on an unglazed porcelain plate.

Photograph a fresh, unweathered surface in daylight, then a second shot of any crystal faces or broken edge. Include a coin for scale. If you did a streak test, photograph the streak next to the specimen. The app suggests the likely mineral or rock; confirm with hardness and the tests above before you label it.

Both the USGS and ASU's Buseck Center for Meteorite Studies advise that these at-home tests can only help with initial screening — they cannot 'confirm a meteorite based on online tests alone.' A true identification requires sending photos to a professional institution (such as the ASU meteorite center, the Smithsonian Institution, or your state geological survey) for further examination.

Meteorite identification from pictures starts with the outside, because that is where the trip through the atmosphere left its marks. These are the features the reference galleries show, with what to look for in your own photo:

• Fusion crust. A thin dark skin, often compared to a charcoal briquette by Geology.com. Washington University in St. Louis notes it is rarely more than 1 to 2 mm thick, because melted rock is stripped away as soon as it forms. In good photos it may look shiny, show contraction cracks, and have chipped spots.
• A lighter interior. Where the crust has chipped off, the inside of a stony meteorite is usually lighter than the crust, a point Washington University repeats across its examples.
• Regmaglypts. Oval dents like thumbprints pressed into clay, common on iron meteorites. The USGS notes iron meteorites are rarely rounded.
• Flow lines. Fine streaks where melted crust flowed during entry, seen on oriented meteorites.
• Chondrules. Small round grains visible on a broken or cut face of stony meteorites.
• Iron meteorites look different. Washington University notes they have a patina rather than a true crust, and no contraction cracks.

Galleries worth comparing against: Meteorite.com shows named irons such as Gibeon and Sikhote-Alin, pallasites such as Brenham and Fukang, and lunar and Martian meteorites; Meteoritetesting.org shows over 130 authenticated meteorites by class.

A photo is better at ruling rocks out than ruling them in. Washington University lists what argues against a meteorite, and the USGS adds more:

• Sharp edges and points. Meteorites are generally rounded at the edges after atmospheric entry.
• Holes and bubbles. The USGS says volcanic rocks and slag often have vesicles and meteorites do not; Washington University adds that the few stony meteorites with holes have sparse, small ones.
• Light-coloured crystals of quartz. The USGS notes quartz is not found on other bodies in the solar system.
• Rough, textured surfaces, or linear fractures and swirls on a broken face.
• A streak. Rubbed on unglazed ceramic, a meteorite should leave no streak, while hematite leaves reddish brown and magnetite grey-black, according to ASU's Buseck Center.

The Meteoritetesting.org gallery includes a 1,130-gram foundry byproduct beside two real meteorites to show how convincing a meteorwrong can look.

The numbers are sobering. Geology.com reports that of the hundreds of suspected meteorites sent in each year, far less than one percent turn out to be genuine. Meteoritetesting.org states simply that from photographs it is not easy to tell, and its own gallery pairs real meteorites with meteorwrongs, including a 1,130-gram foundry byproduct, to show how alike they can look.

The USGS gives the reason: rocks and minerals must be examined in person. It suggests a state geological survey, a natural science museum or a university geology department. ASU's Buseck Center asks people not to send specimens to it.

A photo check is still useful as a first filter. RockLens will name the likely rock, which is often enough to recognise slag, magnetite or basalt and save a trip.

Washington University puts it at about 95% of meteorites attracting a cheap magnet, because they contain iron-nickel metal that Earth rocks do not. The exceptions are rare achondrites, about 2.5% of the roughly 1,500 stony meteorites found in the U.S. The USGS adds a gentler test for weak attraction: hang the magnet on a string, and a stony meteorite may pull it even when the magnet does not stick.

Non-magnetic meteorites include some of the most sought-after, such as lunar and Martian ones, but they are rare: Washington University gives about 9 in 1,000 meteorites from the Moon and 5 in 1,000 from Mars. Because they lack the metal clue, identifying one needs a laboratory. A non-magnetic rock with a crust is far more likely to be a terrestrial rock than a Martian meteorite, so treat the idea with caution until an institution has examined it.

Aerolite Meteorites, a dealer, advises holding iron meteorite and pallasite slices by the edges and not touching the metal with bare hands, because oils from your skin transfer onto the metal surface. It names moisture as the main cause of rust on irons and pallasites.

For a find you have not had identified, that means: keep it dry, do not wash or scrub it, do not cut or grind it, handle it as little as possible, and store it in a dry bag or box. The crust and any chipped surface are exactly what an examiner wants to see.

The sections added on 25 September 2026 were researched and drafted with AI assistance and checked line by line against the sources listed on this page. Statistics come from Washington University in St. Louis, the USGS, ASU and Geology.com; handling advice comes from a meteorite dealer and is labelled as such.

Most meteorites sell by the gram, and the type sets the price. Figures from Geology.com's meteorite value article, read on 25 September 2026:

• Common stony chondrites (unclassified, from the Sahara): from about US$0.50 per gram; attractive ones such as Gao-Guenie about US$1.50 per gram.
• Iron meteorites: premium Sikhote-Alin pieces US$2-3 per gram; a good Campo del Cielo piece about US$400 per kilogram.
• Pallasites (stony-iron) such as Imilac, Glorieta Mountain and Esquel, properly prepared: US$20-40 per gram.
• Rarer stony types: a diogenite such as Tatahouine about US$50 per gram.
• Lunar and Martian meteorites: US$1,000 per gram or more.
• A famous fall: Peekskill, an ordinary H6 chondrite, US$100-200 per gram because of its witnessed fall and story.

Washington University's meteorite team puts it bluntly: a real find is usually not worth as much as its finder hopes.

Four things decide the price, according to Geology.com, and Washington University lists the same kind of factors:

• Type and rarity. An ordinary chondrite is the cheapest kind; lunar, Martian and some achondrites are the most expensive.
• Provenance. A witnessed fall with a documented history, like Peekskill, sells for many times the price of the same type found in a desert.
• Condition. Fresh fusion crust and little rust add value; moisture is the main cause of rust on irons and pallasites, according to the dealer Aerolite Meteorites.
• Looks. Attractive shape, regmaglypts, and on irons a well-prepared etched slice.

None of this applies until the rock is confirmed as a meteorite. The USGS does not verify meteorites itself and sends people to state geological surveys, natural science museums and university geology departments. The dealer site Meteorites-for-sale.com mentions a commercial XRF analysis, which measures the elements in a sample, at about a hundred dollars. Washington University also warns that AI image apps cannot identify meteorites, so treat any photo answer, including ours, as a first screen only.

None of the identification guides we opened, from the USGS, Washington University or meteorite dealers, uses vinegar as a meteorite test. What vinegar does tell you is whether a rock contains calcite: The Stone Circle notes it makes calcite give off small frothy bubbles, while quartz does not react. A rock that fizzes is a carbonate such as limestone, and it still has to pass the tests on this page; vinegar neither proves nor rules out a meteorite.

The acid work on real meteorites is different. Wikipedia describes how iron meteorite slices are ground, polished and then etched with nitric acid or ferric chloride to reveal the Widmanstätten pattern of crossing metal bands; the nickel-rich taenite resists the acid better than the kamacite around it. That is a preparation step for a confirmed iron, not a home identification test.

Do not soak a suspected iron meteorite in vinegar or water. Aerolite Meteorites names moisture as the main cause of rust, cleans rust spots with a rust remover followed by a rinse in alcohol with as little water as possible, and keeps specimens dry.

The USGS says a meteorite scratched on unglazed ceramic should not leave a streak, and that a black or red streak points to magnetite or hematite. The dealer site Meteorites-for-sale.com says meteorites give a brown streak on a test plate. Both agree on what matters most: a black streak suggests magnetite and a dark red one hematite, the two Earth minerals most often mistaken for meteorites. A faint brown mark may come from weathered crust, so test a fresh spot and read it together with the magnet and fusion-crust checks above.