Seven colors radiate from the body: red, orange, yellow, green, blue, purple and indigo. Astrological gems are used in relation to these seven colors. Gems work by absorbing particular colors. Colors can have a subtle effect on a person’s mood, situation, behavior, and destiny. Gemstones have the most condensed form of concentrated color of all elements in the world. The colors that we wear as well as the colors we choose to paint our walls, have an effect upon us. Bright colors tend to brighten our mood, and they indicate the luxuries in and pleasures of life. Dull colors tend to make us more somber. Shades of red represent passion and energy. Light blues and light greens represent peace and calm. White represents purity, innocence, and peace. Light colors are more conducive to sound sleep; bright or dark colors can cause sleep to be restless. Thus each gem and each planet emit particular colors and vibrations. Negative planetary vibrations can be averted, and positive planetary vibrations attracted, by wearing gems of particular colors. Gems have stronger or weaker effects depending on the color emanated and the rate of absorption. The wavelength of the red light emanating from the Sun is the same as the wavelength of the red light emanating from a ruby. Therefore, rubies can help solve afflictions arising from a weak sun in the native’s birth chart. The planets and colors are: Sun - Golden, dark yellow, orange; Moon - White; Mars - Red; Mercury - Green; Jupiter - Yellow; Venus - Rainbow; Saturn - Black, indigo; Rahu - Red, honey; Ketu - Purple.
Power of Colors

(via Eastern Gemology)