A new medium-to-large colour-difference data set (mean DeltaE* = 8.25) using textile samples and a gray-scale method has been produced with the aim of comparing currently available datasets, putting particular emphasis on the characteristics of lightness and hue dependencies of major advanced CIELAB-based colour-difference formulae. The levels of errors in instrumental colour measurements and in visual assessments were similar to those of previous workers. The random and large scattering nature of the trend of unit lightness tolerances with lightness (L*) has made it difficult to apple, a nonlinear lightness weighting calculation, e.g., that of CMC(l:c). The chroma position corrected hue tolerances have shown a weak trend with hue-angle (h(ab)) and it can be incorporated in the existing modified CIELAB formula, e.g., CIE94, to improve its performance. Among the six formulae (CIELAB, CMC, CIE94, LCD, BFD-II, and DCI-95) tested, the LCD (Leeds Colour Difference) formula that is a modified model of the CIE94 colour-difference equation has given the best performance. More visual experimental results are still thought to be required for further development in industrial colour-difference evaluation.