Photoelectron diffraction is proposed to determine nondestructively the polarity of wurtzite crystals with polar surfaces (c-plane). Small segments of polar plots of photoemission from anion core levels in the (10 (1) over bar0) azimuthal plane are qualitatively different for two polarities around the polar angle 20 degrees. The magnitude of the ratio of electron photoemission intensities at two polar angles I-20/I-23 can be utilized as a simple criterion determining the crystal polarity. (C) 2014 Elsevier B.V. All rights reserved.