Preliminary examination of the Yamato-86032 lunar meteorite: II. Major and trace element chemistry
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The chemical composition of the new lunar meteorite Yamato-86032 has been studied by several laboratories in a consortium study. A preliminary report on the first analytical results from seven laboratories is given in this paper. The meteorite, which is the largest lunar meteorite recovered so far, is more heavily shocked than the other five lunar meteorites, which makes it difficult to classify the rock exactly. Although it may be classified as an anorthositic breccia the trace element composition of Y-86032 is somewhat different from the composition of the other known lunar meteorites. The major element chemistry of Y-86032 is similar to the other lunar meteorites, except for the iron content, which is lower by a factor of about 1. 4. Since the magnesium abundance is nearly identical there is a disparity in the mg ratio. The REE abundances in Y-86032 are very low and comparable to Y-82192/3. There is no evidence of any KREEP component. The abundances of several lithophile and incompatible elements are lower in Y-86032 than in the other lunar meteorites. The siderophile element contents are low and vary between individual chips. Sc, Cr, Mn, and Co have significantly lower abundances than in Y-82192/3. The chemical investigations demonstrate that Y-86032 is a new and important sample from the lunar highlands.