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Figure 6
Representative subsolidus phase diagram of the tenary Al–Cu–Fe system at ambient pressure after the work by Bancel (1999BB2). Light grey marks one-phase fields, and tie-lines delimit two-phase regions and three-phase triangles. Dark grey marks the field of icosahedrite. The light brown dash-line triangle indicates the area of the composition space shown in the upper-right inset for a section of the liquidus phase diagram at 882°C after the work by Zhang & Lück (2003BB36). Against this background, data points are shown for the synthetic and natural phase assemblages discussed in this work; symbol shape represents the phase type and colour represents its origin. The contents of minor elements such as Ni and Cr are not reflected in this diagram. The coloured fields connect the co-existing phases in the icosahedrite and i-phase II assemblages. In the Khatyrka meteorite, icosahedrite co-exists with hollisterite and stolperite and defines the dark cyan obtuse triangle. In the same meteorite, i-phase II co-exists with khatyrkite and hollisterite and defines the light cyan triangle. The red field constrained by the shock-synthesized i-phase II assemblage in S1253 is close to that from Khatyrka. The i-phases from other shock experiments are concentrated on the more Cu-deficient side of the diagram.

Volume 7| Part 3| May 2020| Pages 434-444
ISSN: 2052-2525