Amethyst is related to Crown Chakra and the third eye Chakra, primarily is a stone of the mind.
It encourages calm and cool clarity when you feel confused or anxious, makes an excellent meditation stone since it calms emotions and keeps one sharp and alert.
Amethyst is a power crystal. It has been used as protection from self-deception, as well as a protection against negative energies.
The amethyst symbolizes humility, sincerity and spiritual wisdom.
Amethyst is excellent for peace and tranquility. It also balances out highs and lows for emotional and spiritual centering. Wonderful talisman for use in the creative arts, especially in darker shades.
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.
Agate: It transforms negative energy into positive energy. Agate enhances mental function, improves concentration, enhances perception and analytical abilities.
Source: zarasuniverse