How to recognize meteorite.
Not all meteorites are easy to recognize. If they have been for many years on Earth, they may be so weathered which makes them actually impossible to be recognized. Meteorites look different, and it is therefore difficult to give precise guidelines on how to determine if a stone is a meteorite. However, there are some general features that one can go for. Most meteorites will have one or more of the following characteristics:
Black fusion crust
Attracted by the magnet
No bubbles or gas bubbles
Iron meteorites are the easiest to recognize. With a density of 8-9 g / cm3 they are more than twice as heavy as the equivalent normal stone. Iron meteorites are fragments of deviating small planetoids (asteroids) iron cores. Due to collisions between the asteroids, some of these have been totally crushed, and the fragments have been able to spread in the solar system. Freshly Fallen iron meteorites have a distinctive dimpled structure with a cm-large soft indentations and buds. Iron meteorites that are allowed to remain long on earth will eventually be totally corroded by rust and are thus difficult to know.
Freshly fallen meteorites are relatively easy to recognize because of their black (or in rare cases very interesting brownish) fusion crust. Fusion crust is formed when outer layer of the meteorite burning up during the slowdown in the Earth’s atmosphere. The fusion crust is about 1 mm thick, sharply defined against the meteorite’s interior and without crystal grain. The inner parts of the meteorite is not heated in the process of short-term slowdown. If the fusion crust is broken at the time of falling impact, one can see that the interior of the meteorite is light gray to black.
Because of their metal content, most meteorites could be attracted by a magnet. While earth’s stones very rarely contain metal meteorites often contain small metal grains.
A magnet is a good thing to have on hand when you have to examine a meteorite. You should be aware that there are also meteorites without metal content like some of the extremely interesting meteorites from the Moon and Mars.
Chondrites are the most common type of meteorites. They count for about 85% of all meteorites fall on Earth. They have visible metal grains in their interior and are therefore attracted to a magnet. Unless they are completely fresh fallen, the grains are more or less rusty. The interior can also vary in color from light gray to almost black and their fusion crust is matte black.
You can read an interesting article here