According to tradition (including traditional religion) and historically, the colours are:
Kundalini - red, Naval - orange, Solar Plexus - yellow, Heart - green, Throat - blue, 3rd Eye - indigo, and Crown - violet.
It is said that the colours have changed, in the Aquarian Age. These are:
Kundalini (physical body) - red, Naval (astral body) - black & silver, Solar Plexus (vibrational body) - green, Heart (emotional body) - blue & pink, Throat (soul body) - violet, 3rd Eye (psychic body) - orange, and Crown (intellectual body) - yellow & gold.