Each one of us is an individual and "race" as a concept does exist -the human race is one thing but can be divided into many different ethnicities.
Colour is only one of many features that distinguish one individual from another. it is specific to each one of us and has many subtleties. Some are whiter than others, some are darker...Perhaps by describing someones colour in order to individuate them one becomes essentially a colourist and not racist?!
