Green is a healing colour because it represents regeneration and regrowth. In the aura green is positive as it represents a new beginning. . Blue is a colour where the hues can be very important. The lightest colours represent stimulation and mental intuitiveness, the darkest colours can represent melancholia. But all blues represent the informational processes and the brain.
Dark blues are good for calming and soothing and are extremely effective in karma reduction.
But should not be over used. Students often have light blues represented within there auras. It represents the in pouring of energy and the mental activity that they are undergoing. This colour represents the intuitive and spiritual combination of blue and purple. Violet being present in the aura represents a great deal of protection is present.