If you were out prospecting on the side of a hill, and stumbled over a meteorite, would you recognize it? Probably not. Although the earth’s crust is sprinkled with these rare prizes, few of them ever are ever recovered. Like many other rare stones, they have a very drab exterior and the average person on a field trip would not give them a second glance. While it is seldom possible to identify a meteorite by looking at its drab exterior, there are certain characteristics which if understood, will at least give the finder a clue.
Meteorites are of two principal varieties, stony and nickel-iron. A stony meteorite consists mainly of rock material, but in most cases has numerous small grains of nickel-iron distributed all through it. The nickel-iron meteorites are almost solid nickel-iron or steel. These latter are about three times as heavy as ordinary rocks of the same size. The stony meteorites are about one and a half times as heavy as ordinary rocks of the same size. However, there are several kinds of terrestrial rocks or minerals which are quite as heavy, or even heavier, than the stony meteorites. Some of these are magnetite, hematite, limonite, pyrite, chalcopyrite, galena, and certain varieties of basaltic lava. These should not be confused with meteorites.

Another feature of all meteorites is the peculiar crust, covering their surfaces and known as the fusion crust, which has been formed by melting at the surface as they plunge through the atmosphere. When a large shooting-star blazes across the sky, leaving in its wake a train of fire, this train consists of a stream of sparks, which are molten bits or detached fragments of the meteorite, stripped off by the resisting air. This powerful resistance finally slows down the meteorite to a point where it ceases to burn. At this moment the mass is naturally covered with a layer of this molten or fused material which solidifies and becomes the hard black crust which one sees on freshly fallen meteorites.
Stony meteorites contain lumps of material which are harder to melt than the remainder of the mass. These metallic grains and other hard lumps give the stone an uneven surface. This un-eveness shows under the fusion crust, making the meteorite appear much as a lump of concrete would look if it were given a coat of paint. Someone has likened the surface of a brown stony meteorite to the crust of cracked wheat bread. It is a very good comparison. This peculiar crust is one of the best marks by which to recognize meteorites.
There is a third group which is intermediate between the stony and the metallic; these are known as stony-iron or iron-stony meteorites. They consist of about equal portions of stony and metallic material. In these the nickel-iron may be arranged in a network of irregular bands or it may be in the form of more or less disconnected masses embedded in a stony matrix. These metallic constituents may be in the form of very small grains or in larger lumps.

I saw a big one at the Smithsonian natural history museum. It was very cool
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