If I were to choose only one crystal to bring with me on a deserted island, it would be Amethyst. This crystal is by far on the top of my list of metaphysical crystal.
Amethyst is a stone of the spirit. In general, the beautiful purple colour of this crystal is the colour of the spirit and spirituality. Amethyst is also a crystal of protection, selflessness, nobleness, spiritual consciousness, meditativeness, balance and inner peace. One very important feature of Amethyst is to serve as a stone of transfiguration and transformation, bringing harmony and peace wherever needed.
Amethyst represents the most popular variation of naturally coloured quartz. Owing to its magical purple colour, it was highly esteemed in the past. Amethyst improves concentration, memory and other mental abilities. Acting as a means against depression, it helps cure headache and reduce fears. The light of Amethyst calms and relaxes, enabling the person who wears it to clarify the thoughts and achieve inner harmony. Amethyst is used by crystal healers to boost hormone production, stimulate oxygenation of the blood, treat arthritis, and promote good health of the digestive tract, stomach, heart, and skin. It may also help in the case of hearing disorders, insomnia, an overstimulated brain, headaches, migraines, and more.