Calms the mind and puts off the need to feed addictions
Amethyst is a stone of spiritual protection and purification, cleansings one's energy field of negative influences and attachments. Creating a resonant shield of spiritual light around the body.
It acts as a barrier against lower energies, psychic attack, geopathic stress and unhealthy environments.
Secondly, its meaning is protection, most notably protection from addiction. Wearing it calms the mind and puts off the needs to feed the addiction. It offers protection from poison and hostile spirits also.