Many people tell me that they can “see” nickel in their rock. Neither alloy occurs naturally in Earth rocks, so a natural rock that contains kamacite or taenite is a meteorite. The metal occurs as two different alloys known as kamacite (lower nickel concentration) and taenite (higher nickel concentration). “Iron-nickel” means that the metal is mostly iron but it also contains 5-30% nickel. As a consequence, meteorites have concentrations of nickel that are much greater than that of nearly any terrestrial rock. More than 95% of all meteorites contain iron-nickel (FeNi) metal. In proper hands, a hand-held “ XRF gun” can, nondestructively, provide concentrations of Fe, Ni, and Co that might provide compelling evidence that an iron meteorite is, in fact, an iron meteorite. I recommend testing for Cr and Mn because most industrial (man-made) iron contains higher concentrations of these elements than does metal in meteorites. If the metal contains more than 0.05% chromium or manganese, then it is not a meteorite. A metallurgical testing lab can provide this analysis. If you have a piece of metal that does attract a magnet and want to know if it is an iron meteorite, then obtain a chemical analysis for the elements iron (Fe), cobalt (Co), nickel (Ni), chromium (Cr), and manganese (Mn). If you think you can “see gold,” then it is not a meteorite the “gold” is probably just pyrite. Meteorites do not contain visible grains or chunks of nonferrous metals like aluminum, manganese, chromium, copper, brass, or gold. If you have a piece of metal or a rock that contains metal but it does not attract a cheap ceramic magnet ( ferrite), then it is not a meteorite. The metal in meteorites strongly attracts a magnet. We then set each resulting fragment as a very handsome pendant on a silver-plated chain in our Walton, NY fabrication studio. Only about 5% of meteorites are composed of iron! Material of this sort and source is rare, and highly collectible.Back to Some Meteorite Realities Take-home message Each piece is then struck with great force and shattered along those fault lines into fragments, each with a unique shape. Larger pieces of the meteorites are repeatedly heated in hot water to temperatures above 150 degrees Fahrenheit, and cooled in liquid nitrogen to temperatures below -300 degrees Fahrenheit, in order to weaken them along natural fault lines formed in the undisturbed void of outer space over billions of years. Scientists believe that, like other iron meteorites, the Campo del Cielo mass probably originated within the Asteroid Belt located between Mars and Jupiter. The total weight of the pieces recovered so far from Campo del Cielo exceeds 100 tons, making the meteorite the heaviest one ever recorded on Earth. These craters were first “discovered” by a Spanish military expedition in 1576 they were, however, already known to the aboriginal inhabitants of the area. The craters are estimated to be between 4,000 and 5,000 years old. The crater field covers an area of approximately 35 square miles, and contains at least 26 craters (the largest being a little more than 6 square miles around). The Campo del Cielo refers to a group of iron meteorites, and to the area where they were found, 620 miles northwest of Buenos Aires, Argentina.

Campo del cielo meteorite