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)
SS Empire Amethyst at Belfast to allow a crew member to be discharged through illness and a replacement to be taken on board. On reaching Freetown, "Empire Amethyst" sailed for New Orleans. In mid-April 1942, "Empire Amethyst" left New Orleans bound for Freetown carrying a cargo of 12,000 tons of motor spirit. Her intended route took her via the Lesser Antilles and then across the Atlantic to Freetown. "Empire Amethyst" was spotted by the crew of on 12 April 1942. The U-boat captain, Walther Kölle, believed that she was being escorted by and did not attack. At 03:02 hrs "Empire Amethyst" received a