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) American ship attempting to dock in a French port. This may have been "Caroline", captured on 14 April. In early June Cooke met up with Captain Sir Edward Pellew's squadron at Quiberon Bay. The squadron engaged in a successful large scale raid on Morbihan, though "Amethyst"s role, if any, is unclear. "Amethyst" was among the vessels of a squadron that shared the proceeds for the recapture on 28 June 1800 of "Lancaster". She was also part of Pellew's squadron, which shared in the proceeds of the capture of "Vigilant", "Menais", "Insolent", "Ann", and the wreck of a vessel that was