Examples of X-ray-selected galaxy clusters in the X-CLASS survey. Top panels: cluster Xclass0561 (ABELL 2050) at z = 0.119 as confirmed by 19 member galaxies. Bottom panels: cluster Xclass0219 at z = 0.791 as confirmed by 11 member galaxies. Left panels: X-ray images and contours. Green circles (squares) mark detections of extended (point-like) sources as classified by the XAmin pipeline. Straight lines that cross the image are CCD gaps of the XMM-Newton detector. Right panels: i-band optical images from PanSTARRS over-plotted with X-ray contours. Red circles mark the member galaxies with available spectroscopic redshift. In the case of Xclass0561, both X-ray and optical images cover the same sky area, while in the case of Xclass0219 the optical image corresponds to the central region of the X-ray image marked with the black square.