Watson 017        30°36’19.2"S, 131°33’21.1"E

South Australia, Australia

Find: 2015 Apr 12

Classification: Ordinary chondrite (H5)

History: Initial fragments found by R. Stokes on a claypan. Further fragments, followed by two main masses were found over a ~30 m2 area, by the Monash team.

Physical characteristics: Numerous <5 cm fragments were found, almost none showing fusion crust. Two main mass fragments were found next to each other, the largest being 532 g. It has extensive weathering cracks, with loose fragments in the final stages of flaking off. These two masses were covered in lichen and had 40% fusion crust.

Petrography: (A. Tait, Monash) Sample contains both Type I and Type II chondrules. Chondrule edges are poorly defined, although a few relict chondrules do exist with well-defined edges, they appear to be fragmented. Chondrule types observed are: BO, POP, RP, PO. The matrix is opaque and extensively recrystallized, no large (>50 μm) secondary feldspars were observed. FeNi metal and trolite exhibits moderate ~30% oxidation around the perimeter of the meteorite. The center of the meteorite shows higher oxidation (~80%) with some corrosion cavities, and extensive wreathing veins. Most olivinea show undulous extinction, approximately 5-10% of olivines show shock lamellae, no higher shock indicators are present.

Geochemistry: (A. Tait, A. Landendam, Monash) FEG-SEM analyses show that olivine and pyroxene compositions are uniform: olivine Fa_17.9-19.7, mean= Fa_18.0±0.9, n=14; Low-Ca pyroxene Fs_15.0-18.7Wo_1.1-1.9, mean= Fs_16.3±1.0Wo_1.3±0.3, n=13.

Classification: Ordinary Chondrite (H5, S3, W3)

Specimens: All fragments, main mass and a thin section at Monash.