Amethyst is the purple variety of Quartz. The purple colouration is due to ferrous iron impurities. Amethyst is found worldwide. 
Amethyst is a powerful and protective crystal, and is a first choice of many metaphysicians. Amethyst was used in ancient times to recover from both physical addictions as well as addictive relationships, and became known as the “stone of sobriety”. 
A natural stress reliever, Amethyst encourages and supports inner strength. 
The strong healing energy of Amethyst can transmute lower vibrations to higher frequencies, transforming negative energy to love energy. 
Amethyst connects the physical plane with higher realm, making it a good choice when working with the Third Eye Chakra. Amethyst also provides a wonderful peaceful energy for meditations, and helps with developing intuition and psychic abilities. 
Amethyst opens and activates the Crown Chakra, allowing easier access to the divine. Amethyst enhances spiritual awareness and spiritual wisdom, promoting a higher state of consciousness. Amethyst clears and repairs holes in the aura and draws in Divine energy, as well as aligning and fostering cooperation between the energy bodies. 
Physically, Amethyst can help to alleviate headaches and migraines. It dispels nightmares and helps with insomnia. Amethyst can also reduce eyestrain, especially when working at a computer. 
Please note: that over time Amethyst will fade in the sunlight.