Meteorites and Their Properties


VIII. Tests for Suspected Meteorite Specimens

To help determine if an unusual rock is a candidate for further examination, a set of questions is listed below which identify the most prominent characteristics of meteorites.

  1. Does the sample have a black or brown surface? (Please, do not clean the surface or remove any adhering crust on a suspected meteorite sample.)
  2. Is the sample solid, without pores or hollow vesicles?
  3. Is the sample heavy for its size? Iron meteorites are very dense compared to most rocks on the Earth's surface.
  4. If a corner of the sample is ground slightly, is the interior metallic silver?
  5. Is the sample unlike other rocks in the area?
  6. Is the sample magnetic? Does it attract a magnet or deflect a compass needle?

If you were able to answer "yes" to all of these questions, then your sample is a good iron meteorite candidate and warrants further examination. If you were able to answer yes to the first, fifth, and sixth questions, and the sample resembles one of the stones shown in Section III, then it too warrants further examination.

If you have a sample that is a candidate for further study, you should take it to your local science museum or university.

If after taking your sample to a museum or university you are notified that it is not a meteorite, you should not be discouraged. Many geologic processes, particularly volcanism, produce rocks with properties grossly similar to those of meteorites. Often a terrestrial rock and a meteorite can only be distinguished by subtle properties that may be obvious only to an expert. The types of terrestrial rocks that are often confused with meteorites include (1) those covered with desert varnish, which is a dark coating resembling fusion crust but which is produced in part by bacteria in arid regions; (2) volcanic magnetite or other types of iron oxide minerals which are dense and have brown surfaces; (3) slag, which are odd-shaped lumps of metal often confused with iron meteorites, but which were produced by mining and foundry operations; (4) ventifacts, which have surfaces that have been winnowed by wind and sand and may resemble meteorites with oriented ablation surfaces or fusion crusts; and (5) Apache tears, which resemble tektites but are really spherical remnants of glassy volcanic lava flows. Because of the difficulty in distinguishing meteorites and related objects from some terrestrial materials, you should not hesitate to contact your local museum or university if you have another sample that satisfies the criteria outlined above.


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