Tuesday, November 13, 2012
Meteroties Part II
Widmanstäten patterns in meteorites are caused by slow cooling from about 700°C to 450°C slowly. The mineral make up of the meteorite (before it hit earth) would have to be mostly iron with about 15% nickel. Theoretically, the slow cooling process could happen in an asteroid. The Widmanstäten lines only occur in nickel-iron meteorites.
There are lots of types of meteorites and they are all based on their chemical composition. But for the most part they can be grouped into two other types; stony-iron & stony.
Stony-iron meteorites are meteorites that are made of stone iron mixed with some kind of stone. Because they look like regular plain rocks, they are not as easy to find in nature. In fact, most never are.
Stony meteorites are even less obvious. They are just plain rocks with little to no special characteristics about them.