MOUNT MAGNET


Iron, IAB complex, sHH subgroup
standby for mount magnet photo
Found 1916
28° 2' S., 117° 58' E.

Two fragments constituting a single sickle-shaped mass having a combined weight of 16.5 kg were found in Western Australia, about 10 km east of Mount Magnet (Buchwald, 1975). The mass exhibits significant terrestrial weathering with no evidence of fusion crust or heat-affected zone. Mount Magnet is classified structurally as a plessitic octahedrite (Opl) with kamacite needles of a few µm in size. This iron was initially classified as geochemically anomalous, but has since been included in the high-Au, high-Ni subgroup of the IAB complex (Wasson and Kallemeyn, 2002).

The interior structure of Mount Magnet is ataxitic, containing numerous ribbons of schreibersite, small grains and clusters of silicates, and monocrystalline grains of troilite—each of these inclusions are often rimmed by kamacite. Both small pockets and skeletal crystals of schreibersite are also present, the former usually surrounded by wide kamacite rims. The photo shown above is an 11.32 g partial slice of Mount Magnet.