How to Identify a Meteorite: Signs, Lookalikes and What to Do Next
Meteorites updates · Practical guide · Sources checked 26 October 2026
How do you identify a meteorite? Start with careful observations, a record of where the object was found, and comparison with documented specimens. A black surface, unusual weight or magnetic attraction can be a clue, but none proves that a rock came from space. Preserve the object while you decide whether expert examination is worthwhile.
This guide explains the clues and helps you preserve useful evidence. It does not identify a reader’s specimen from a photograph.
1. Understand what you are trying to identify
A meteorite is material from space that survives passage through an atmosphere and reaches the ground. Most meteorites recovered on Earth come from asteroids; some are pieces of the Moon or Mars. A meteor is the light-producing atmospheric event, rather than the specimen in your hand. These distinctions explain why seeing a bright streak does not identify a nearby rock. See the NASA Science facts page for background.
Identification and classification are separate questions. First establish whether the material is extraterrestrial. Only then can a specialist evaluate which meteorite group it belongs to. “Looks like a Martian meteorite” skips both steps.
2. Look for several clues together
A fusion crust is a thin surface layer formed when the outside melts during atmospheric entry. A relatively fresh example may be dark and fairly smooth. Weathering can change its colour or remove it. A dark coating alone is weak evidence: some Earth rocks develop dark surface coatings too.
Regmaglypts are shallow, thumbprint-like depressions associated with atmospheric shaping. Do not confuse them with a frothy network of gas bubbles. Many gas cavities, called vesicles, more commonly suggest volcanic rock or industrial slag. These are useful comparisons, not a universal identification formula. USGS outlines common field clues.
A specimen may feel heavy because it contains dense minerals or metal. Earth materials can do this too. Compare like-sized objects carefully rather than treating “heavy” as a measurement. Some meteorites contain obvious metal; others do not. You cannot determine nickel content simply by seeing a shiny patch.
3. Learn the common meteorite lookalikes
Slag is a by-product of industrial melting. It can be dark, heavy, magnetic and apparently melted. Magnetite and hematite are common terrestrial iron-bearing minerals that also cause confusion. A rock’s presence in an isolated place does not exclude industrial material: old transport routes and fill can move it far from its source.
Arizona State University’s meteorite and lookalike guide explains why simple checklist rules have exceptions. In particular, weathered meteorites can differ from the fresh specimens pictured in books. Search-result photographs should help you ask better questions, not supply a certificate of authenticity.
Illustration: clues overlap
Meteorite crust or an Earth-rock coating?
Meteorite metal or dense terrestrial minerals?
Meteorite phases or an iron-rich lookalike?
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Record the evidence → Preserve the specimen → Seek appropriate examination
A possible match remains unconfirmed.
4. Avoid the hand-magnet trap
Many meteorites respond to magnets, but so do several Earth materials. A positive result therefore does not prove origin, and weak attraction does not settle the question either. More importantly, applying a hand magnet can overwrite natural magnetic information that researchers may want to study.
The 2023 study “Hand Magnets and the Destruction of Ancient Meteorite Magnetism” examined this problem using modelling, experiments and Martian meteorite samples. Avoid bringing a hand magnet to a potential find. If you already used one, record that honestly; the history can still help later interpretation.
5. Make a useful specimen record
Photograph the object as found, then photograph the whole specimen from several directions with a ruler beside it. Record the date, location, surroundings and whether it was moved. Keep exact location details in your own record. Separate observations from guesses: “dark brown exterior” is an observation; “fusion crust” is an interpretation that needs support.
Do not wash, oil, brush, grind, cut, heat or chemically test the object while seeking advice. Such actions change evidence. The Washington University identification guidance stresses useful photographs and warns against cleaning with abrasives or chemicals. This article deliberately avoids home streak, cutting and acid procedures.
6. Ask about examination before sending anything
Check a museum’s, university’s or geological survey’s current acceptance policy before contacting it or posting a specimen. Some organizations provide information but do not accept public submissions. For example, ASU’s published identification policy says its public identification programme is suspended and unsolicited specimens are not accepted.
If a qualified examiner recommends analysis, ask what question the method answers, whether sampling is destructive, and what the result can establish. A mineral name, a metal reading or an unexplained commercial certificate is not automatically a meteorite classification.
Quick answers
Can a phone app confirm my meteorite? No. Image matching can suggest comparisons, but it does not supply the physical and analytical evidence needed for confirmation.
Should I begin by asking its price? Begin with identity and documentation. A sale estimate for an unverified rock cannot establish what it is.
What is a good next step today? Make a clear photo record and compare it with expert reference material before changing the object or paying for a test.
Continue learning
Read Module 5: Basic Meteorite Identification, Module 6: Recovery and Documentation, and the complete course contents. More articles appear in Meteorites updates.
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