More than 500 years after the secret was lost, a British scientist claims to have rediscovered the method by which ancient Romans created the regal purple dye – a color emblematic of the togas worn by emperors, as well as the sails on Cleopatra’s ship.
Purple dye is one of the oldest dyes known to humanity. Derived from the murex snail, it became the symbolic color of power for Roman emperors after Nero. However, the secret to producing this dye has been lost since 1453.
John Edmonds, a retired engineer, discovered this secret while researching the fermentation process of indigo dye from the woad plant. “I believe the imperial purple dye also undergoes a fermentation process similar to that of indigo,” Edmonds stated. He experimented by using small snails closely related to the murex and fermented the purple dye in a vessel of water mixed with wood ash. These snails contain important bacteria essential for decolorizing the dye. The mixture was maintained at a temperature of 50 degrees Celsius for 10 days. Wool dipped in the dye turned light green, but when exposed to light, it transformed into purple.
Recreating this ancient dyeing method has significant applications today. Currently, tons of chemicals used to decolorize denim have released large amounts of sulfur. Utilizing bacteria as an alternative to chemicals could help develop a clean dyeing technology in the future.
Minh Thi
