Abstract Under the current classification scheme, ungrouped irons make up ~11% of all recognized iron meteorites. A further ~7% of iron meteorites are currently classified as simply “irons” and are yet to be fully classified. To potentially classify these meteorites, newer approaches, including either statistical modeling or advanced geochemical/petrological characterization, may be required. To approach this issue, we studied three ungrouped iron meteorites from Western Australia—Pennyweight, Prospector Pool, and Redfields. We conducted petrographical and geochemical analyses using a TESCAN Integrated Mineral Analyzer (TIMA), electron backscattered diffraction (EBSD), and laser ablation inductively coupled mass spectrometry (LA‐ICP‐MS). Through these analyses, the modal abundances, orientation relationships, and geochemical properties of the key metallic phases were determined. From this work, we have found that spot analyses of the kamacite and plessite are sufficient for iron meteorite classification, and these values can be used to reconstruct a “bulk” geochemical composition. Additionally, statistical data reduction (principal component analysis and t‐distributed stochastic neighbor embedding) models have been used, in conjunction with the traditional logarithmic element plots, to assist with classification. Our results agree with previous studies that recommend the reclassification of Prospector Pool to the IIE group. Pennyweight may be a mesosiderite metal nodule with a metal composition closer to the IIIAB and IIE meteorites but has petrographical features similar to the IIE irons. It should remain ungrouped at this stage. Redfields is most likely a member of the IAB complex, potentially an IAB anomalous meteorite. Finally, the statistical models show a dichotomy between the IAB group and that the current iron meteorite groups seem to have more geochemical similarities than differences. Further analysis is required to assess the validity of the current classification scheme.
Rogers et al. (Fri,) studied this question.