A ‣ Words and expressions for specific colours 
pitch black: intensely black, used about darkness, night, etc. (pitch is an old word for tar)
jet black: intensely black, used about hair, eyes, etc. (jet is a black semi-precious gemstone)
scarlet: very bright red
crimson: strong deep red
shocking pink: an extremely bright pink
ginger: orangey red, used about hair and animal fur
navy: dark blue, used about clothes, not eyes
turquoise: greenish blue, used about fabrics, paint, sea, etc. but not usually eyes
lime: a bright yellowish green
beige: a light creamy brown
mousy: a light, not very interesting brown, used only about hair
chestnut: a deep reddish brown, used about hair and horses
auburn: a red-brown colour, usually used about hair
A number of words for gemstones are also used as colour adjectives, e.g. ruby [deep red], emerald [bright green], amber [yellowy orange], coral [orangey pink], sapphire [deep blue], jade [dark green].
B ‣ Words for talking about colour 
Red, blue and yellow are primary colours; by mixing them together you can make other colours. Pastel colours are pale shades of colour – pink, mauve [pale purple] and pale yellow, for example. Strong colours are the opposite of pastels. Harsh colours are colours that are unpleasantly strong. Vivid colours are strong, bright colours like scarlet or turquoise. Fluorescent colours are very bright colours which seem to glow in the dark. Electric blues or greens are extremely bright blues or greens. If white has a tinge of green, there is a very slight shade of green in it. If something is monochrome, it uses only one (or shades of one) colour, e.g. black, white and grey. The suffixes -y and -ish show that a colour is partly present, e.g. bluey green, reddish brown.
C ‣ Colour metaphors 
blue = depression (to feel blue); physical or unskilled (blue-collar workers)
red = anger (to see red = to be very angry); danger (red alert, a red flag); special importance (All the competitors were given the red-carpet treatment. The day we met will always be a red-letter day for me.); communist or very left-wing in politics (People’s views sometimes become less red as they get older.)
green = nausea (to look green) (People who are seasick often turn/go green and sometimes vomit.); envy (She turned green with envy when she saw her friend’s new car.); care for the environment (green tourism; the Green Party)
black = depressing or without hope (a black future); anger (to look as black as thunder); illegality or incorrectness (black market, black sheep of the family, black mark) (During the war people bought many goods illegally on the black market. If I don’t finish this report in time, that’ll be another black mark against my name. My brother was the black sheep of the family, leaving school and home at the earliest opportunity.)
grey = lack of clarity (a grey area); brains (grey matter, grey cells)
white = purity (white as snow, whiter than white); being pale (She was so shocked that she went white as a sheet.); a white-knuckle [terrifying] ride at an amusement park such as Disneyland; office workers (white-collar workers)