The Chessy test specimen comprises more than 1.6 million gold squares on silicon which form a four-fold chequerboard pattern in an area of 5mm square. The pattern is directly written in a resist using e-beam lithography techniques. The overall Size of specimen is 10 mm x 10 mm. The smallest chequerboard on this sample has a size of 10 x 10 µm. These smaller chequerboards then form larger chequerboards of 100 x 100µm - these again form larger chequerboards of 1mm2. Finally the 1mm squares are arranged in the same style covering a field of 5mm2. The edges of the empty corners in the 100 x 100µm chequerboards are additionally marked. The surrounding frame is 10µm wide and has an outer side length of 5.04mm. This test sample is suitable for the calibration of SEM magnification in all ranges between x20 and x50,000. It can also be used for checks of orthogonality and distortion and the positional calibration of motorised stages.