Knardna 001        31° 0’18.70"S, 130°54’18.60"E

South Australia, Australia

Purchased: 2012 May 16

Classification: Ordinary chondrite (H4)

History: Fragment found by J. Kuyken on claypan.

Physical characteristics: Broken desert-red fragment with 15% fusion crust.

Petrography: (L. Bowlt, Monash) This sample contains chondrules that are highly fragmented and poorly defined, as well as chondrules that make sharp contact with the surrounding matrix. The chondrules range in size up to 2 mm (average 0.2-1 mm). There are distinct light/dark areas at the sub-centimeter scale corresponding to two differing types of matrix; the majority of the sample contains recrystallised matrix and there are two areas that have an optically opaque matrix associated with shock blackening. Minerals include olivine, pyroxene, plagioclase (1-2 microns), Fe-Ni metal and troilite. Chondrules are relatively abundant (20-25%) and chondrule types include RP, BO, PO, PP and POP. Olivine grains show undulose extinction and shock lamellae. 60-70% of metal and troilite have been oxidised with the remaining 30-40% divided up between 30-35% sulphides and 5-10% metal grains.

Geochemistry: (L. Bowlt, Monash) Microprobe analyses show that olivine and pyroxene compositions are uniform: olivine Fa_16.9-17.7, mean= 17.3 mol%, std= 0.38, n=4; Low-Ca pyroxene Fs _14.8-15.9, mean= 15.48 mol%, std= 0.45, n=4.

Classification: Ordinary Chondrite (H4 , S3, W3)

Specimens: Specimen and one thin-section held by A. Tomkins.