Hexaplex trunculus degrades, resulting in blue only. Nonetheless, archeologists have confirmed Hexaplex trunculus as the species used to create the purple-blue dye; large numbers of shells were recovered from inside ancient live-storage chambers that were used for harvesting. Apparently, 10- to 12,000 murex yielded only one gram of dye. Because of this, the dye was highly prized. Also known as "Royal Purple", it was prohibitively expensive and was only used by the highest ranking aristocracy. A similar dye, "Tyrian purple", which is purple-red in color, was made from a related species of marine snail, "Murex brandaris". This dye (alternatively known as "imperial
HMS Tyrian (R67) HMS Tyrian (R67) HMS "Tyrian" was a S-class destroyer built for the Royal Navy during the Second World War. "Tyrian" displaced at standard load and at deep load. She had an overall length of , a beam of and a deep draught of . She was powered by two Parsons geared steam turbines, each driving one propeller shaft, using steam provided by two Admiralty three-drum boilers. The turbines developed a total of and gave a maximum speed of . "Tyrian" carried a maximum of of fuel oil that gave her a range of at . Her complement was 170 officers