Composition and origin of holotype Al-Cu-Zn minerals in relation to quasicrystals in the Khatyrka meteorite.
Last update: 26 June 2018
Ivanova, M. A., Lorenz, C. A., Borisovskiy, S. E., Burmistrov, A. A., Korost, D. V., Korochantsev, A. V., Logunova, M. N., Shornikov, S. I. and Petaev, M. I.
Meteoritics & Planetary Science.
Version of Record online: 14 FEB 2017
“We investigated the khatyrkite–cupalite holotype sample, 1.2 × 0.5 mm across. It consists of khatyrkite (Cu,Zn)Al2, cupalite (Cu,Zn)Al, and interstitial material with approximate composition (Zn,Cu)Al3. All mineral phases of the holotype sample contain Zn and lack Fe that distinguishes them from khatyrkite and cupalite in the Khatyrka meteorite particles (Bindi et al. , , , ; MacPherson et al. ; Hollister et al. ). Neither highly fractionated natural systems nor geo- or cosmochemical processes capable of forming the holotype sample are known so far. The bulk chemistry and thermal history of khatyrkite–cupalite assemblage in the holotype sample hint for its possible industrial origin. Likewise, the aluminides in the Khatyrka meteorite particles may also be derived from industrial materials and mixed with extraterrestrial matter during gold prospecting in the Listvenitovy Stream valley.”
Reply to the comment by Andronicos et al. (2017) on “Composition and origin of holotype Al‐Cu‐Zn minerals in relation to quasicrystals in the Khatyrka meteorite” by Ivanova et al. (2017)
M. A. Ivanova, C. A. Lorenz, S. E. Borisovskiy, A. V. Korochantsev, M. N. Logunova, M. I. Petaev
Meteoritics & Planetary ScienceFirst published: 25 May 2018
Comment on “Composition and origin of holotype Al‐Cu‐Zn minerals in relation to quasicrystals in the Khatyrka meteorite” by M. Ivanova et al. (*), C. L. Andronicos, L. Bindi, V. V. Distler, L. S. Hollister, C. Lin, G. J. MacPherson, P. J. Steinhardt, M. Yudovskaya
“”Ivanova et al. (2017) proposed that the aluminides we described in the Khatyrka meteorite fragments, both crystal and quasicrystal metal phases, were derived from industrial materials used during placer gold mining and that these had been shredded and blast‐propelled into natural meteoritic material that happened to be at the site. The blast hypothesis was not supported by evidence that metal shrapnel or metal parts from mining operations (or from any other industrial use) occur at the site that are similar in composition to the aluminides that we described in Khatyrka; we doubt such compositions would exist because alloys with the compositions we reported have no known industrial applications. We further show that this hypothesis cannot be reconciled geologically, chemically, or physically with our observations. These observations demonstrate that the fragments central to our study have been embedded below gold‐bearing fluvial gravels in undisturbed sediment for at least ~6670 to 8004 14C years before mining operations commenced. The case presented here thus specifically rules out the blast hypothesis and also presents a challenge to other anthropogenic explanations. We also address each of Ivanova et al.’s points challenging our conclusion that the silicates attached to the aluminides were CV3 chondritic minerals.”