Color was always used with care in Egyptian composition, and it is generally significant. Our understanding of ancient usage, however, is complicated by the fact that the Egyptians appear not to have classified colors in the same way as we do today.

Light blue, for example, seems to have been associated with green or white rather than seen as a shade of dark blue, which the Egyptians evidently related to black. This difference in perception may explain the use of light blue for the flesh of the normally green-skinned god Ptah in this pectoral ornament from the Treasury - and similarly the use of black for both the blue crown of the king and the god's close-fitting cap.