The color purple is the Kahuna of all colors in the spectrum. Ok... maybe that is just my opinion.. and Jimi Hendrix's .
It is the color worn by magicians and royalty. It has the highest vibration on the color spectrum. The amethyst stone is often used for healing and transmutation. Well known to absorb and dissolve negativity which helps against stress and nightmares. Works at all levels, mind, body and spirit.
It is immortalized in the poem, "When I Am An Old Lady I Shall Wear Purple" and the uniform of the crazy ladies of the Red Hat Society.