Types of Metal Detecting Activities, page 37:


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Meteorite Identification & Authentication

The simplest way to identify a meteorite in the field is to use a quality magnet since 95% of all meteorites are magnetic and will be attracted to it. You can also distinguish a meteorite from terrestrial objects by its weight (meteorites are dense and will feel heavier than ordinary rocks), "fusion crust" (a thin, hard black outer layer acquired during burning in the atmosphere; meteorites appear much darker than ordinary rocks), and surface features (flowlines and "regmaglypts" (thumbprints) formed during melting of meteorite's surface, and angular features such as points and ridges).

Orientation is another feature unique to meteorites. When a meteorite keeps a fixed orientation towards the surface of the earth, it sometimes melts into a cone or bullet-shaped object. Such highly oriented specimens are very rare and highly sought by collectors.

When examining a suspected meteorite, keep in mind that most terrestrial rocks do not have shiny metal and minerals in the shape of small spheres. If you chip or grind away a small portion of your find and see the shiny iron/nickel metal or flakes (in stone meteorites), or chondrules (minerals in the shape of small spheres), most likely you have got a meteorite.

But be aware of false meteorites or meteorite look-alikes, especially when you are planning to buy a meteorite for your collection, such as the following: amethyst crystals, basalt, furnace slag, sandstone, fulgurites (glass formed by a lightning strike in sand), lava, obsidian, asphalt, pudding stone, and tektites (they lack a fusion crust, even though often exhibiting regmaglypts). If not sure, conduct other methods of meteorite identification.

A very effective method for meteorite identification with use of a metal detector (White's XLT) is described in details on my "How To Distinguish a Meteorite from Terrestrial Objects" page.

The following are several organizations and individuals, some with their websites, that not only buy and sell meteorites, but also can help identify suspected meteorites:

• New England Meteoritical Society (Mendon, MA)
• Bethany Sciences (New Haven Connecticut)
• Smithsonian Institute (Washington, D.C.)
• Center for Meteorite Study (Arizona State Univ., Tempe, Arizona)
• Mare Meteorites (Oakland, CA)
• MMR Inc. (San Jose, CA)
• Robert Haag (Tucson, AZ)
• Walter Zeitschel (Hanau, Germany)
• Swiss Meteorite Lab (Glarus, Switzerland).

Also, for a small fee, most university planetary science departments or a licensed mineral testing laboratory will conduct an accurate final analysis. At last, there are informative and educational books on meteorite detecting that can help you attain knowledge about meteorites. The most popular are "Rocks From Space" by O. Richard Norton and "History of Meteorites" by Astronomical Research.

If you happen to see when and where a meteorite hit the earth (a witnessed fall) and you are the first person reporting it, a California based organization – Star Trackers (POB 5743-F, Montecito, CA 93150), will pay you a $100 reward. For that, your find must be authenticated with a fragment analysis, and the site location has to be verified. The earliest postmarked letter will be used in the event when more than one person reports the same impact site.

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