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Apollo 16 sample 60635 is a plagioclase-rich, coarse-grained impact melt. Geochemical analyses of its plagioclase crystals show an enrichment in light-REE in comparison to other Apollo 16 impact melt samples and over half of the analyses display a negative Eu anomaly suggesting that this sample may have assimilated a target rich in quartz-monzogabbro or similar lithology. Recently, analyses of 2 additional samples (60235,5 & 60335,13) from the vicinity of the Lunar Module (LM) have also displayed a negative Eu anomaly suggesting that 60635,2 is not unique. Although 60635 was collected as a rake sample ~70 m W-SW of the (LM), near a subdued 150 m diameter crater, samples 60235 and 60335 were both collected within the crater ~ 15 m SW and ~55 m NE of the LM respectively. However, while plagioclase crystals with negative Eu anomalies are prevalent in 60635, only one analysis from each 60235 and 60335 exhibits such a signature. Additionally, whole rock analyses from 60635 and 60335 exhibit negative Eu anomalies which is unexpected given the amount of plagioclase in the samples. The whole rock analyses are consistent with other samples collected near the LM that display a similar whole rock signature (e.g., the glass coatings of regolith breccias, soils, and at least one poikilitic impact melt) suggesting that the anomalous signature from 60635, 60235, and 60335 may be indicative of the LM site as a whole. We are currently conducting geochemical (whole-rock and mineral) and textural analyses on several more samples from around the LM to determine the extent of this signature.
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