Great! However, identifying a meteorite can be tricky. There are a lot of misconceptions about meteorites that can lead the layperson to “false positive” identification. Over the years of examining potential meteorites brought in by enthusiastic amateur meteorite hunters, we’ve found less than 1% to be actual meteorites. In fact, in the last two decades, only five samples have tested positive through our analyses. We examine about 10 samples in person every month.
So, how can you better assess whether or not your rock is extraterrestrial in origin? Here are some brief tips that you should consider before bringing your sample to us. See if you can distinguish the meteorite from the meteorwrong.
It’s probably NOT a meteorite if…
it appears "burned"
the inside of it is the same color as its surface
it has holes in it
it has flat sides, geometric shape, or is spherical
There are many processes on the Earth’s surface that form spherical rocks but these processes do not occur where most meteorites originate. Meteorites are also, in general, not rectangular or square and they do not have flat sides. As a meteorite falls through the atmosphere, the edges and corners are the first things that melt. This process is similar to leaving an ice cube to melt in water. The edges and points of the cube are the first things to melt away.
it looks metallic, but is not very strongly magnetic
All iron meteorites will attract a magnet. The vast majority of meteorites will attract a magnet to some degree.
it has layers
Layers are formed on Earth because of gravity. The vast majority of meteorites come from asteroids that are too small to have any appreciable gravity.
Most meteorites should have the following properties. However, many minerals and rocks from Earth also share these properties, so don’t get TOO excited…
- Strongly magnetic
- Very dense (they feel heavy for their size)
- Possess a fusion crust, which is a thin, dark, glassy coating that will appear different from the material within the rock. Often, fusion crust will be textured with numerous “thumbprint” indentations called regmaclypts, which are produced from friction with air as the meteorite enters the atmosphere.
Before filling out a form for an appointment, please read the following statements describing the services we offer:
What to do if you would like us to examine your specimen:
Due to the sheer number of requests we DO NOT accept any samples by mail, nor do we identify samples from emailed photographs. We will examine possible meteorites only if they are brought directly to us at TCU. Walk-in appointments are not offered as the Curator has to be available to analyze your sample.
What we will and will not do at an appointment:
Appointments typically last only ten minutes. We will examine your sample and give you our opinion on whether or not it is a meteorite. We may conduct some tests but these will not affect your sample in any way. There is no charge for our time. We DO NOT offer an appraisal service. If your sample is not a meteorite, which is the most likely outcome, we will do our best to identify what it actually is; however, we are meteorite experts and there are many weird and wonderful rocks both natural and man-made that can be found on this beautiful planet of ours and we just don’t know them all. You are always welcome to seek a second opinion elsewhere, we are only human.
How you make an appointment:
The Curator, Dr. Mayne, offers meteorite identification afternoons one Friday a month.