Amethyst element impurities), and the presence of trace elements, which result in complex crystal lattice substitutions. The hardness of the mineral is the same as quartz, thus it is suitable for use in jewelry. Amethyst occurs in primary hues from a light pinkish violet to a deep purple. Amethyst may exhibit one or both secondary hues, red and blue. The best varieties of amethyst can be found in Siberia, Sri Lanka, Brazil and the far East. The ideal grade is called "Deep Siberian" and has a primary purple hue of around 75–80%, with 15–20% blue and (depending on the light source)
HMS Amethyst (1799) officers finally permitted the press gang from "Immortalite" to board, all they found on board were a few sickly sailors. Some seven months later, on 11 November 1803 "Amethyst" captured "Spes", H. L. Cornelia, master. Three days later, "Amethyst" captured "Johannes". That same day "Amethyst" captured "Irene", L. J. Lubbens, master. In June 1804, a court martial dismissed Campbell from command of "Amethyst" and stripped him of all his seniority on the Captain's List for misconduct in an action with four Dutch vessels off the coast of Norway. Command transferred to Captain John Spranger. On 24 July "Amethyst", while in