MesosideriteOne of two main types of stony-iron meteorite, the other being pallasites. Mesosiderites are a mixture of approximately 50% basaltic, gabbroic and orthopyroxenitic silicates and 50% Ni-Fe metal and sulfides. The name derives from the Greek "mesos" meaning "middle" or "half" and "sideros" for "iron;" hence "half-iron". The silicates are, group 2A
Found 1985
no coordinates recorded Two fragments with a combined weight of ~7 kg were found near the village of Gillio, Libya by an oil worker. The masses were utilized as bookends until they were purchased from the worker’s daughter by meteoriteWork in progress. A solid natural object reaching a planet’s surface from interplanetary space. Solid portion of a meteoroid that survives its fall to Earth, or some other body. Meteorites are classified as stony meteorites, iron meteorites, and stony-iron meteorites. These groups are further divided according to their mineralogy and dealer A. Lang in 1998. A sample was submitted to Rutgers University (Roger Hewins) for analysis and classification, and the name Sahara 85001 chosen to be most appropriate given the lack of an exact findMeteorite not seen to fall, but recovered at some later date. For example, many finds from Antarctica fell 10,000 to 700,000 years ago. location. However, results were not forthcoming, and four years later, an additional sample was submitted to Northern Arizona University (Ted Bunch). By this time in 2002, the NWA-series had been established by the Meteorite Nomenclature Committee of the Meteoritical Society and the name NWA 1242 was assigned to this mesosiderite; however, since it is a find location in Libya, this meteorite was included within the NWA-series. In the interim a couple of kilos of this meteorite was sold under the name Sahara 85001, and this name is now a synonym for the official name NWA 1242. Northwest Africa 1242 was classified at Northern Arizona University as a member of the small 2A metamorphicRocks that have recrystallized in a solid state due to changes in temperature, pressure, and chemical environment. subgroup. (see the Bondoc page for further information about the Floran (1978) and Hewins (1984) classification schemes).
Photos courtesy of Alan Lang—R. A. Langheinrich Meteorites