Amethyst
Amethyst is a master stone, and a highly protective crystal. It physically represents the alchemic violet ray of transformations. This stone is for the sixth and seventh chakra. It has a range of practical applications. Big amethyst stones (druse and geode) are commonly used in health centers, meditation rooms, and waiting rooms. It fills the space with soothing vibrations, neutralizing negative energy and liberating blocked energy. The darker the amethyst, the stronger its effect.