Au thin films deposited on (111) YSZ single-crystal substrates were dewetted and equilibrated in a low oxygen partial pressure (10(-20) atm) at 950 degrees C. Electron backscattered diffraction of 150 equilibrated Au particles shows that there is no preferred low-index orientation relationship (in-plane orientation relationship) but rather a strong preferred orientation of {111} Au parallel to {111} YSZ. This result is associated with identical interface energies (1.75 +/- 0.02 J/m(2)) measured using Winterbottom analysis from three equilibrated Au particles with different orientation relationships with the YSZ substrate. Energy dispersive spectroscopy in a scanning transmission electron microscope of the interfaces showed a Ca excess of Gamma = 1.65 +/- 0.20 atoms/nm(2) (detection limit of 0.12 atoms/nm(2)). It is believed that Ca segregation reduces the interface energy of the system, resulting in a more isotropic orientation distribution instead of a low-index orientation relationship normally seen between fcc metals and YSZ.