analyzing the color using reflectance according to an exemplary embodiment of the present invention as a reference sample a coated color and uncoated color of the pantone book may be used the reference object may be a cu u2014 sn alloy a cu u2014 zn alloy a cu u2014 ni alloy or a cu u2014 si alloy and may be a sample for which the wavelength wise reflectance for each composition was measured using the spectrophotometer alternatively an electronic recording medium in which the information on the composition and wavelength wise reflectance of an alloy and the color of the alloy are electronically recorded may be used in the graph of fig2 the measurement result of the comparison values of the wavelength wise reflectance with respect to 877c and cu62_tin38 was shown to be less than 0 05 from these results 877c and cu62_tin38 may be determined to be the same color by the same token 877u and cu62_tin38 may be determined to be the same color from the graph of fig2 877c 877u and cu62_tin38 may be determined to be the same color the wavelength wise reflectance can be measured with respect to a different color alloy in the same manner as in example 1 fig3 shows a graph illustrating the measurement results of wavelength wise reflectance according to another exemplary embodiment of the present invention fig3 shows the results of wavelength wise reflectance measured using a spectrophotometer.