¹Ajay Dev Asokan,¹Yogita Kadlag,²Yash Srivastava,³Khirod Kumar Das,³Rumanshu Hazarika,²James M. D. Day
Meteoritics & Planetary Science (in Press) Link to Article [https://doi.org/10.1111/maps.70099]
¹Geosciences Division, Physical Research Laboratory, Ahmedabad, Gujarat, India
²Scripps Institution of Oceanography, San Diego, California, USA
³Department of Geology, Babasaheb Bhimrao Ambedkar University, Lucknow, India
Published by arrangement with John Wiley & Sons

The Holocene Luna Structure in western India has been claimed to be the fourthand youngest impact crater on the Indian subcontinent. The circular shape; the unusualmineralogy including high-temperature mineral phases such as kirschsteinite and w€ustite;and the elevated abundance of highly siderophile elements (HSE: Os, Ir, Ru, Rh, Pt, andPd) have been provided as evidence in favor of an impact origin. Here, we present newmineralogical, bulk rock geochemical data including isotope-dilution HSE abundances and187 Re- 187 Os compositions of the suspected Luna impactites. The samples are dense irregularnodules with undulated surface and flow-like structures and are glassy to extremely finegrained, with or without vesicles. The new HSE data show no Ir enrichment compared toupper continental crust. The radiogenic measured 187 Os/ 188 Os compositions (0.2289–0.7253)further rule out any extraterrestrial contribution in the suspected impactites. The observedhigh-temperature mineral assemblage shows similarity to that of iron-rich archaeologicalslags. We reinterpret the Luna Structure materials as slags that are likely associated with theBronze Age in the Harappan Civilization and may have formed as a byproduct of coppersmelting. Considering the new evidence, the Luna Structure of western India is not ameteorite impact crater.