This paper was to synthesize a ceramic pigment of tetragonal Nd 2 Si 2 O 7 by the Pechini sol–gel method and subsequent thermal treatment. The crystallization processes of the pigment precursors with and without LiCl of 5 wt.% as a mineralizer were investigated by X-ray diffraction and thermogravimetry-differential thermal analysis, respectively. The results show that LiCl can promote the formation of monoclinic Nd 2 Si 2 O 7 transient phase at a lower heat-treated temperature. The color properties of pigment samples were measured in color space CIE L*a*b* under different standard illuminants (i.e., solar-light D 65 , incandescent light A, cool white fluorescent lamp F2, and three-band fluorescent lamp F11). The color changes of Nd 2 Si 2 O 7 pigment under different illuminants were also characterized quantitatively via the color difference analysis. The maximum value of the color difference between D 65 and F11 can reach 12.65, implying that Nd 2 Si 2 O 7 pigment could be used as a functional ceramic pigment with “allochroic effect”. In addition, the mechanism of color change under various light sources was also discussed.