The Campo del Cielo Meteorite is Coarse octahedrite in structure, and while it hasn’t been classified as an iron meteorite, iron is what most of its composition is. Campo del Cielo is classified as in the I chemical group, but others have classified it in the IAB class as well. A mass of Campo del Cielo known as “El Chaco” is one of the heaviest meteorites on Earth as it weighs 37,000 tons; its weight is second only to the Hoba Meteorite.
Campo del Cielo was officially discovered in 1576, when Captain de Miraval led a Spanish-funded expedition to what is now Buenos Aires. In the area known as Campo del Cielo, Miraval’s first find came to be the stuff of legends: Meson de Fierro (large table of iron). Miraval would return to Spain and tell stories about the massive Meson de Fierro, which enticed the Spanish to send more expeditions. Unfortunately, by the time Miraval returned, Meson de Fierro was gone. For several centuries, explorers would search for Meson de Fierro and never find it; no one knows how it vanished or even if Miraval was lying about its existence. Today, Meson de Fierro would quite possibly be worth tens of millions if sold to a museum.
More so than the actual masses, the Campo del Cielo meteorite is known for its 22 impact craters. It’s from these craters that most reliable information about Campo del Cielo derives—the most definite information gathered is the date of Campo del Cielo’s fall, which was during a period of history that many meteorites fell known as the Holocene period. This would put Campo del Cielo’s age at an estimated 4,000-5,600 years, making it an “infant meteorite” in comparison to other meteorites that are in excess of 4 billion years in age.
Like many meteorites, Campo del Cielo’s existence was known of by natives of the area long before it was officially discovered and reported. There is no documented indication that Campo del Cielo masses were used by the native Indians to create tools or weapons; the first documented instance of the Campo del Cielo meteorite being used for this purpose was not until the 1800’s, when a pair of flintlock pistols allegedly made from Campo del Cielo were given to American president James Monroe.
The closest anyone has possibly come to finding and transporting Meson de Fierro would be American meteorite collector and dealer Rober Haag, whom was arrested in 1992 for attempting to leave Argentina with a 37 ton meteorite in tow. The authorities did not recognize Mr. Haag’s claimed ownership, and the 37 ton meteorite remains in Argentina.
As of 2009, individuals still travel to Argentina and Buenos Aires trying to find this possibly-fabled stone.