Meteorites Explained: Basic Types and Identification Clues
A dark, heavy rock can spark an exciting question: could it have come from space? Meteorites are fascinating, but many ordinary rocks and industrial materials resemble them.
This guide introduces the main types and useful identification clues. No photograph, magnet test, or single surface feature can confirm that an unknown rock is a meteorite.
The three basic types
Stony meteorites
Stony meteorites consist mainly of silicate minerals. Some contain small grains of iron-nickel metal. Chondrites are an important group of stony meteorites; many contain small rounded mineral structures called chondrules. Other stony meteorites, called achondrites, have different textures and histories.
Iron meteorites
Iron meteorites consist mainly of iron-nickel metal. They can look very different depending on weathering and preparation. A whole specimen’s exterior won’t necessarily resemble a cut and prepared interior.
Stony-iron meteorites
Stony-iron meteorites contain substantial amounts of both metal and silicate minerals. Pallasites are a striking example, with olivine crystals set within metal. Not every stony-iron meteorite has that appearance.
Clues worth examining
Fusion crust: Many stony meteorites have a thin outer layer formed as their surface melted during atmospheric entry. Weathering can change or remove it. A dark coating alone is not proof.
Metal: Some meteorites contain visible iron-nickel metal grains. However, terrestrial rocks and industrial materials can contain metal too.
Weight: Some meteorites feel unusually heavy for their size, particularly iron meteorites. Dense Earth rocks can feel heavy as well.
Surface depressions: Some meteorites have shallow, thumbprint-like depressions called regmaglypts. These are not the same as the abundant bubble holes often seen in slag.
Magnetic attraction: Many meteorites attract a magnet, but so do many ordinary rocks and manufactured materials. Magnetic attraction cannot establish an extraterrestrial origin, and some meteorites show little attraction.
Common lookalikes
Industrial slag is frequently mistaken for meteorite material. It may be dark, heavy, metallic, and attracted to a magnet. Glassy surfaces and numerous gas-bubble cavities are useful warning signs.
Iron-rich terrestrial rocks and manufactured metal can also look convincing. An unusual appearance is a reason to investigate, not a diagnosis.
What to do with a possible find
Photograph it clearly in good light, with a scale, and record where and when you found it. Keep any loose fragments together.
Avoid cutting, grinding, acid-testing, or aggressively cleaning it before seeking advice. Contact a geology department, natural history museum, or meteorite specialist to ask whether they offer identification or can recommend an appropriate service. Confirmation may require laboratory examination.
Buying your first meteorite
Look for a named specimen, a clear description, its classification, and reliable information about its origin. Ask what documentation comes with it and whether it has been cut, etched, coated, or otherwise prepared.
A certificate is useful only when its claims are backed by a trustworthy source. Choose a seller who can explain what the specimen is and how it was identified.
A small specimen with good documentation can be a rewarding introduction to meteorites. You don’t need the largest piece to enjoy owning something extraordinary.
Use our contact form if you’d like help choosing a specimen.