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) HMS Amethyst (1799) HMS "Amethyst" was a Royal Navy 36-gun "Penelope"-class fifth-rate frigate, launched in 1799 at Deptford. "Amethyst" served in the French Revolutionary Wars and the Napoleonic Wars, capturing several prizes. She also participated in two boat actions and two ship actions that won her crew clasps to the Naval General Service Medal. She was broken up in 1811 after suffering severe damage in a storm. "Amethyst" was commissioned in May 1799 under the command of Captain John Cooke. She then operated on the Dutch coast later that year. During the Anglo-Russian invasion of Holland, "Amethyst" conveyed the Duke