The distinction between cold and warm colours is very old, rooted in the language about colours (Berlin & Kay, 1969) and is perceptually important. Psychological research at the University of Padua into the cold / warm qualities of colours shows that the subjective colour temperature experience changes abruptly when the limit of the hue values ​​above 120° in the CIELAB colour system has been exceeded. The same sudden change occurs around 330° (da Pos & Valenti, 2007). A clear correlation has been established between cold / warm and hue values ​​(Jin, Eun & You, 2003). This agreement also appears to work cross-culturally (Sato, Xin & Hansuebsai, 2003). The cold / warm contrast is related to the perceived light in a landscape. The “warm” colours are associated with daylight or sunset, and the “cold” colours associated with a gray or dark day. Warm colours are the shades of red-violet to yellow, cool colours are the shades that run from blue-green through blue-violet.

Light colours eg. pastel shades, are felt lighter in weight than dark colours.

(Meerwein, 2007)

T-tests indicated that black was judged significantly heavier than the modulus assigned to white. Apparent weight is a decreasing non-linear function of value. Value and chroma are the major determinants of colour weight. Apparent weight is a decreasing function of value and an increasing function of chroma. These results support the earlier qualitative findings that “dark” colours appear heavier than “light” colours, while providing quantitative meaning to the terms dark and light. The reason that colours appear to have different weights is not clear. Bullough (1907) first offered the reasonable suggestion that the apparent density of colours determines their apparent weight just as the actual density of objects determines their physical weight. Colour weight would then be another example of a synesthetic interaction between sense modalities, in this case between vision and kinesthesis (see Marks, 1975). According to this scheme. hue, value. and chroma would interact to determine colour density; then colour density would determine colour weight by a process of synesthesia. An appropriate test of this model would involve sensory scaling of the various attributes of colour. (Alexander & Shansky, 1976)