Amethyst and it can not be differentiated with absolute certainty without advanced gemmological testing (which is often cost-prohibitive). There is one test based on "Brazil law twinning" (a form of quartz twinning where right and left hand quartz structures are combined in a single crystal) which can be used to identify synthetic amethyst rather easily. It is possible to synthesize twinned amethyst, but this type is not available in large quantities in the market. Single-crystal quartz is very desirable in the industry, particularly for keeping the regular vibrations necessary for quartz movements in watches and clocks, which is where a lot
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