1) Color 2) Coloring material 3) Colour 4) Colouring material 
Hematochrome is a yellow, orange, or (most commonly) red biological pigment present in some green algae, especially when exposed to intense light. It is a name used mainly in older literature. Hematochrome is a mixture of carotenoid pigments and their derivates. ...
[n] - a reddish coloring material found in some algae