![]() ![]() Iron meteorites are far heavier than most earth rocks-if you've ever lifted They are among the densest materials on earth and will stick very strongly to a powerful Iron meteorites were once part of the core of a long-vanished planet or large asteroidĪnd are believed to have originated within the Asteroid Belt between Mars and Jupiter. ![]() Up and their reaction is, almost without fail, to exclaim: "Wow, it's so heavy!" Most people have never held a space rock in their handsĪnd when someone does pick up an iron meteorite for the first time their face lights Museums, and schools, I always enjoy commencing the presentation by passing around a When I give lectures and slideshows about meteorites to rock and mineral societies, Photo by Geoffrey Notkin, copyright Aerolite Meteorites. This specimen is also highly oriented, with a textbook snub-nosed leading edge (pictured) and a flat back. Note the glossy black fusion crust, and fine flow lines which were caused as the surface of the meteorite melted during flight. Eucrites are volcanic rocks from other bodies in the solar system, and Millbillillie is one of the very few meteorites which does not contain iron-nickel. It was a witnessed fall (1960) and is a rare type of achondrite-a stone meteorite which does not contain chondrules. Stone Meteorite: A 56.5-gram complete individual of the Millbillillie eucrite from Australia. Much of meteorite classification is based, in fact, on how much iron a Rocks, we usually discount anything that does not contain significant amounts of Rare that when we are asked for help and advice on identifying possible space Almost all meteorites containĮxtraterrestrial nickel and iron, and those that contain no iron at all are so Three main groups: irons, stones and stony-irons. The Three Main Types of MeteoritesĪlthough there are a large number of sub classes, meteorites are divided into The Sikhote-Alin shower was the largest recorded witnessed meteorite fall in history. Its surface is covered with scores of small regmaglypts, or thumbprints, created by melting during flight. This fine specimen is described as a complete individual, as it flew through the atmosphere in one piece, without fragmenting. Iron Meteorite: A superb 1,363-gram complete iron meteorite from the Sikhote-Alin meteorite shower which occurred in a remote part of eastern Siberia in the winter of 1947. To stone meteorites, especially the most abundant stone meteorite group-the Though irons may be synonymous with most people's perception of a typical space rock's appearance, they are only one of three main meteorite types, and rather uncommon compared Very heavy, and have often been forged into unusual or even spectacular shapesĪs they plummet, melting, through our planet's atmosphere. It is often said that when the average person imagines what a meteorite looks The lattice-like structure is known as a Widmanstätten Pattern after Count Alois von Beckh Widmanstätten who described the phenomenon in the early 1800s. The slice has been etched with a mild solution of nitric acid to reveal an interlocking pattern of iron-nickel alloys, taenite and kamacite. Iron Meteorite: Detail of a polished and etched slice from a siderite (iron) meteorite found in the Brenham, Kansas strewnfield in 2005 by professional meteorite hunter Steve Arnold. ![]()
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