The high-temperature Knudsen effusion method was used to study partial pressures of vapour species, activities of components and the Gibbs free energies in the DyF 3 -Dy 2 O 3 system at the temperature (1357 AE 5) K. Partial pressures of the vapour species were obtained by the ion current comparison method, with the DyF 3 partial vapour pressure over pure DyF 3 as a standard. The equilibrium constant of the gaseous reaction DyF 3 DyOF = Dy 2 OF 4 was evaluated. Thermodynamic data obtained are in a agreement with the available phase diagram of the DyF 3 -Dy 2 O 3 system. Results of the present study illustrate the negative deviations from the ideal behaviour in the system. #

We investigated the khatyrkite-cupalite holotype sample, 1.2 9 0.5 mm across. It consists of khatyrkite (Cu,Zn)Al 2 , cupalite (Cu,Zn)Al, and interstitial material with approximate composition (Zn,Cu)Al 3 . 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. 2009(Bindi et al. , 2011(Bindi et al. , 2012(Bindi et al. , 2015MacPherson et al. 2013;Hollister et al. 2014). 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.

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