Most "iron" meteorites are iron-nickel alloy with a few scattered inclusions of sulfide minerals. The alloys are 5 to 12 percent nickel, with traces of cobalt, chromium, gold, platinum, iridium, tungsten and other elements that dissolved in the molten iron and traveled with it to the parent body's tri.
On Earth's surface, gold and platinum are rare elements because they sank to the core here just as they did in other differentiated bodies. The relatively rich concentrations of these elements in irons from asteroids raises the possibility of someday mining asteroids for precious metals. Asteroids could also provide a virtually unlimited supply of steel for building spacecraft and space stations.
Topic: Earth Science
Keywords: Meteorites, Iron-nickel alloys, Minerals, Mines and mineral resources, Astrogeology, Asteroids