Amethyst is crystalline quartz found most commonly in Brazil,Canada and East Africa. With a relatively high hardness of 7, the February birthstone  for all purposes. 
BENEFICIAL FOR  : Decision making,anger,rage,fear, grief,anxiety,dreams,alcoholism,emotional and psychological pain , hearing disorder and stress .
Amethyst protects against psychic attack, paranormal harm or ill-wishing, and returns the energy back to the universe after being transformed into positive, loving energy.
AMETHYST : Came from the Greek for to be intoxicated  and worn to be sober . Also encourages selflessness and spiritual wisdom . It is one of the stone most used by healers.