Crystalline quartz in shades of purple, lilac, or mauve is called Amethyse, a stone traditionally worn to guard against drunkness, and to instill a sober and serious mind.
Amethyse is dichroic, showing a bluish or reddish purple tinge when viewed from different angles. Usually faceted as a mixed-or step cut, amethyst has distinctive inclusions which look like tiger-stripes, thumbprints, or feathers. Some Amethyse is heat-treated to change color to yellow,producing citrine.
