![]() ![]() ~95% of meteorites contain between ~10 and ~20% metallic iron when they fall. What do those meteorites look like? Well… Weathered meteorites Most meteorites found on Earth have spent thousands of years here, just waiting to be picked up. But most meteorites that are found didn’t fall recently. ![]() So, right after they fall, most meteorites have a black crust on the outside, and they range from ~white to ~black on the inside. So, we’ll skip the details on diogenites and visually ~similar meteorites. ![]() However, these meteorites are exceedingly rare, and only a dozen or so have been seen to fall in recorded history. There are also a few exceptions to the grey-black gradient - namely with pale green meteorites made mostly of olivine or pyroxene. There are a few other details you might have noticed…a few have started to oxidize (3rd, 6th images). As you can see, they range from ~light grey to black inside. Most of the broken stones fragmented in the atmosphere or when they landed on a hard surface. The above album contains freshly-fallen meteorites. The last molten material on the rock’s surface cools and solidifies on the outside of the meteorite, forming a “ fusion crust.” This layer is usually fairly smooth, but is not the polished texture of a water-worn pebble. As the fragments are slowed down by the atmosphere, their surfaces begin to cool. If any rocks do survive the passage, they almost always bear some scars. The body is usually broken up by extreme ram pressures, and the fragments begin to ablate as well. The outside of the meteorite vaporizes, and a thin molten layer forms on the outside of the rock. This causes intense heat and pressure to act on the surface of the rock. For comparison, the Space Shuttle used to enter the upper atmosphere at ~8 kilometers per second. Usually ~ 20 to 40 kilometers per second. When meteorites enter the atmosphere, they’re moving really quickly. But there are a few things you can look for. There are many different types of meteorites, and an even wider variety of rocks from Earth. Maybe someone has approached you with a rock they think is a meteorite, hoping to sell it. Staff who are glad to help with mineral identification.Maybe you’ve just found a strange rock, or maybe you’ve had one laying around for years. To more complicated either in procedure or concept, can be found here:īutte, Montana is home to a beautiful mineral museum ( ), which is free to the public (donation encouraged), and is run by a knowledgeable Tests in a suggested order, progressing from simple experimentation and observation In the field or at home, while others require laboratory equipment. Many of these tests can be performed easily The physical properties of minerals (color, hardness, density, etc.) are used to helpĭetermine the identity of a specimen. (Information from )Īdditional online resources for visual investigation of meteorites: However, this crust weathers to a rustyīrown color after several years of exposure on the Earth's surface and will eventuallyĭisappear altogether. It is often blackĪnd looks like an eggshell coating the rock. The Earth's atmosphere a very thin layer on the outer surface melts. This is because when a meteorite falls through Meteorites that have fallen recently may have a black "ash-like" crust on their surface, ![]()
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