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)
HMT Amethyst from a sunken German craft. HMT Amethyst HMT "Amethyst" was a naval trawler requisitioned by the Admiralty prior to the Second World War. She was sunk in the second year of the war. "Amethyst" was built as the commercial trawler "Phyllis Rosalie" by Smiths Dock Company, South Bank-on-Tees and was launched on 15 January 1934. Her first owners were the Boston Deep Sea Fishing & Ice Co Ltd, based at Fleetwood. In 1935 she set a number of records for catches landed at Fleetwood, and was present at HM King George V's Silver Jubilee Spithead Review, representing the port of