![]() ![]() Rocks in the desert will sometimes develop a shiny black exterior that looks similar to fusion crust.The fusion crust may look like a black eggshell coating the rock.If your rock does not have a fusion crust, it is most likely not a meteorite.A fusion crust will most likely be smooth and featureless, though it may also include ripple marks and "droplets" where molten stone had moved and resolidified.government agency responsible for conducting scientific research on the nation's land, natural resources, and natural disasters Go to source If your rock’s surface looks like it has melted and shifted, it may be a meteorite. As rocks pass through the Earth’s atmosphere, their surfaces begin to melt and air pressure forces the molten material back, leaving a featureless, melt-like surface called a fusion crust. Does your sample cause a streak on a “streak plate?” If not, you may have a meteorite.Determine whether the rock has a fusion crust. If the sample is magnetic and leaves a black or gray streak, then it might be the common terrestrial iron-oxide mineral called magnetite. If you drag your sample across this “streak plate,” and it leaves a red/orange line, then the sample is probably a common mineral on the Earth called hematite. Most meteorites won’t leave a streak, but the surfaces of some meteorites might leave a reddish streak if they have been oxidized (rusted). ![]() Does your sample have Regmaglypt texture/thumbprints? If so, you have a meteorite. The surface of most meteorite samples have these thumbprints called “regmaglypts,” which can vary in size from less than a centimeter up to as much as 10 centimeters. This leaves a bunch of small dents in the surface of the rock, making it look like someone put thumbprints into clay. When the surface of the meteorite begins to melt during entry into the atmosphere, some areas of the meteorites are eroded by the melting more than others, almost like someone is taking little scoops of material out. Does your sample have a fusion crust? If so, you have a meteorite. Small patches of fusion crust can sometimes remain in hollows of the sample. Fusion crusts are present on freshly fallen meteorites, but the crusts are fragile and can weather away from samples that fell a long time ago. Iron meteorites may show evidence of melted metal on their surface, but this is less common. The meteor gets so hot that the outer surface begins to melt, which produces a thin black/brown coating on the surface of the rock called a fusion crust. When a meteorite is falling through the atmosphere, it begins to heat up because of the extreme compression of the atmosphere. Does your sample contain chondrules? If it does, you might have a meteorite. Some sedimentary and volcanic rocks can have spherical particles that look somewhat like chondrules. These little round pieces are called chondrules. Some primitive meteorites have little round pieces of stony material in them. ![]() So, just because something is magnetic, it doesn't mean that it is a meteorite. But remember that a lot of normal rocks on the Earth are also magnetic. Is a magnet attracted to the surface of your sample? If so, you might have a meteorite. Magnetic Properties - A lot of meteorites contain shiny iron-nickel metal grains or consist largely of iron-nickel metal.
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