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 meteorite 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 find 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 metamorphic subgroup. (see the Bondoc page for further information about the Floran (1978) and Hewins (1984) classification schemes).
Northwest Africa 1242 contains scattered, cm-sized, metal nodules (see photo below), together with lithic clasts consisting of Ca-rich pyroxene, anorthitic plagioclase, pyrrhotite, chromite, and FeNi-metal. This unweathered mesosiderite (W0) is shocked to stage S1. The specimen shown above is an 11.67 g partial slice. The top photo below is a close-up image of a large, etched metal nodule, while the bottom photo shows the main mass of NWA 1242.