Most are brecciated and many show broken and irregular inclusions of silicate minerals, rich in magnesium. Mesosiderites take their name from the Greek words for "iron" and "half" and are comprised of approximately equal amounts of nickel-iron and stony components. Mesosiderites may appear to some collectors and enthusiasts as ugly ducklings when compared to their beautiful cousins, the pallasites. Photograph by Steve Arnold, copyright Aerolite Meteorites.Ĭlick to enlarge. The open, lightĬolored surfaces are ideal for rockhounding, and the Atacama has produced It is one of the most barrenĭeserts on earth, with almost no plant or animal life. Vaca Muerta strewnfield: The author scans the Vaca Muerta strewnfield with binoculars during our 1997Įxpedition across Chile's Atacama Desert. After the meteorite was recovered and examined, the olivine crystals it contained were determined to be of such a high quality that gems from the Marjalahti pallasite were adopted as the official standard for peridot. It is one of only three witnessed-fall pallasites in existence. In 1902 a 45-kg meteorite known as Marjalahti fell in the Respublika Kareliya in Russia. Photograph by Leigh Anne DelRay, copyright Aerolite Meteorites. Corroded specimens such as this are unofficially called
Much of the iron-nickel has terrestrialized, while the olivine crystals This Brenham piece was found in a damp, muddy part of the strewnfield and Institutional trade with the NHM and brought it back to the United States. This piece was part of a largeĬollection that Nininger sold to the Natural History Museum in London after This specimen has an interesting history: It was recovered in the 1930s inīrenham, Kansas during an expedition by the pioneering American meteorite Weathered Brenham meteorite: A highly weathered example of a small Brenham meteorite with a broken face. In other words, stony-irons consist of a mixture of nickel-iron and silicates. They contain roughly equal parts of the other two classes. Compared to the other two main groups, stony-irons are extremely rare, making up less than 2% of all known meteorites. Although many contain flecks of extraterrestrial nickel-iron as well as chondrules they do, in many respects, look similar to terrestrial rocks. Stones are the most abundant type of meteorite, and most once comprised part of the crust of bodies within the Asteroid Belt. What Are Stony-Iron Meteorites?Īs discussed in previous editions of Meteorwritings, iron meteorites are composed primarily of iron and nickel, and once formed part of the core of planets or large asteroids. Photograph by Geoffrey Notkin, copyright Aerolite Meteorites. Yellow due to terrestrial weathering, while the crystals nearer to theĬenter of the original mass have retained their true olive green color. In which crystals near the rough (natural) edge have turned orange and
Large, colorful, oblong crystals are typical of this meteorite. Esquel pallasite: A part slice of the lovely Esquel pallasite from Chubut, Argentina.
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