The Cape York meteorite, also known as the Innaanganeq meteorite, is one of the largest known iron meteorites, classified as a medium octahedrite in chemical group IIIAB. In addition to many small fragments, at least eight large fragments with a total mass of 58 tonnes have been recovered,[2] the largest weighing 31 tonnes (31 long tons; 34 short tons). The meteorite is named after the location where the largest fragment was found: 23 miles (37 km) east of Cape York, in Savissivik, Meteorite Island, Greenland.
The meteorite fell to Earth after the retreat of glaciers from the area. All fragments recovered were found at the surface, partly buried, some on unstable terrain. The largest fragment was recovered in an area where the landscape consists of "flowing" gravel or clay-like sediments on permafrost, indicating that it had been in place for no more than a few thousand years.[2] Other estimates have put the date of the fall as 10,000 years ago.[3]
The iron masses were known to Inuit as Saviksoah (Great Iron, later renamed Ahnighito by Robert Edwin Peary)[4] weighing 31 metric tons (31 long tons; 34 short tons); the Woman, weighing 3 metric tons (3.0 long tons; 3.3 short tons); and the Dog, weighing 400 kilograms (880 lb).[5] For centuries, Inuit living near the meteorites used them as a source of metal for tools and harpoons.[6][7] The Inuit would work the metal using cold forging—that is, by hammering the metal with stones. Excavations of a Norse farm in 1976 located an arrowhead made of iron from the meteorite, dating from the 11th to 14th century AD; its presence is evidence of Norse journeys to northern Greenland.[2] Other pieces of Cape York meteoritic iron dating prior to 1450 (i.e. before the Little Ice Age) have been found throughout the Arctic Archipelago and on the North American mainland, and are evidence of an extensive Thule culture trade network[8]: 52 which supplied iron to First Nations peoples prior to European contact.[8]: 105
A lance made from a narwhal tusk with an iron head made from the Cape York meteorite
In 1818, the British First Ross Expedition (led by Captain John Ross) made contact with Inuit on the northern shore of Melville Bay, who stated they had settled in the area to exploit a nearby source of iron.[2] The Inuit described the location of this iron, but poor weather and sea ice prevented Ross from investigating further.[2] Ross correctly surmised that the large iron rocks described by the Inuit were meteorites, and purchased several tools with blades made of the meteoritic iron.[2]
Peary with the Ahnighito fragment
Between 1818 and 1883, five further expeditions to the area were mounted by Britain, Sweden, and Denmark, which all failed to find the source of the iron.[2] Only in 1894 did a Western explorer reach the meteorite: Robert E. Peary, of the US Navy.[2] Peary enlisted the help of a local Inuit guide, who brought him to Saviksoah Island, just off northern Greenland's Cape York. Peary dedicated three years[citation needed] to planning and executing the removal of the meteorite, a process which required the building of a short railroad.[citation needed] Peary sold the pieces for $40,000 (equivalent to $1.41 million in 2022[9]) to the American Museum of Natural History in New York City, where they are still on display. The 3.4-by-2.1-by-1.7-metre (11.2 ft × 6.9 ft × 5.6 ft) piece named Ahnighito is on display in the Arthur Ross Hall of the American Museum of Natural History. Ahnighito is the second-heaviest meteorite to have been relocated. It is so heavy that it was necessary to build its display stand so that the supports reached directly to the bedrock below the museum.[10]
In 1963, a fourth major piece of the Cape York meteorite was discovered by Vagn Buchwald [da; de] on Agpalilik peninsula.[5] The Agpalilik meteorite [da], also known as the Man, weighs about 20 metric tons (20 long tons; 22 short tons), and it is currently on display in the Geological Museum of the University of Copenhagen, Denmark. Other smaller pieces have also been found, such as the 3 metric tons (3.0 long tons; 3.3 short tons) Savik I meteorite found in 1911 and the 250 kilograms (550 lb) Tunorput fragment found in 1984. Surveys of the area with a magnetometer in 2012 and georadar in 2014 found no evidence of further large iron fragments, either buried or on the surface.[2]
Slice of Agpalilik in the Geological Museum in Copenhagen
Agpalilik outside the Geological Museum in Copenhagen
Composition and classification
It is an iron meteorite (medium octahedrite) and belongs to the chemical group IIIAB.[1]
There are abundant elongated troilite nodules. The troilite nodules contain inclusions of chromite, sulfides, phosphates, silica and copper. The rare nitride mineral carlsbergite (CrN) occurs within the matrix of the metal phase. Graphite was not observed and the nitrogen isotopes are in disequilibrium.[14] The meteoric iron is identifiable by a very high nickel content.[15]
^Rickard, T. A. (1941). "The Use of Meteoric Iron". Journal of the Royal Anthropological Institute. 71 (1/2): 55–66. doi:10.2307/2844401. JSTOR2844401.
^Buchwald, V. F. (1992). "On the Use of Iron by the Eskimos in Greenland". Materials Characterization. 29 (2): 139–176. doi:10.1016/1044-5803(92)90112-U.
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