In the ancient world, Tyrian purple was the most sought-after and expensive color. Produced from large quantities of sea snails, this precious pigment was reserved for use by the upper class. The process of producing Tyrian purple was complex and required collecting thousands of sea snails to create just 1 gram of dye. This made it an extremely valuable commodity in Roman times, even more valuable than gold.
Recently, archaeologists and volunteers discovered an extremely rare object during an excavation of a Roman bath in Carlisle, northern England. The object, made of a soft purple substance, contained beeswax and the element bromine. Analysis showed that this is a solid sample of Tyrian purple dye – a highly valuable artificial pigment in ancient times.
Sarah Irving, a spokeswoman for Cumberland Council, which collaborated with Wardell Armstrong on the excavation project, said that the Tyrian purple dye sample at Carlisle was likely used to paint frescoes. This pigment can also be used to paint walls in large public buildings, homes and real estate of the upper class, and sometimes to dye clothes.
The Phoenicians first produced Tyrian purple in the 2nd millennium BC in Tire – a city in Lebanon and one of the world’s oldest continuously inhabited settlements. It is also produced in some other areas of the Mediterranean such as North Africa. Frank Giecco, an archaeologist with mining consultancy Wardell Armstrong who participated in the excavation at Carlisle stated that finding a solid specimen like this blob is particularly unusual as it is only known from Northern Europe and possibly even from all over the Roman empire.