In the city of Carlisle, England, an extremely rare object was discovered by archaeologists and volunteers during an excavation of a Roman bath. The object, made of a soft purple substance, contained beeswax and the element bromine, indicating that it is a solid sample of Tyrian purple dye – a highly valuable artificial pigment in ancient times.
Producing Tyrian purple was a complex process that required collecting thousands of sea snails. Experts estimate that up to 12,000 snails needed to be processed to create just 1 gram of dye. This substance was so expensive in Roman times that it was even more valuable than gold and reserved for use by the upper class.
Tyrian purple has been one of the most sought-after colors in the world for millennia. According to Frank Giecco, an archaeologist with mining consultancy Wardell Armstrong who participated in the excavation at Carlisle, this is the only example known from Northern Europe and possibly even the only example from any region within the Roman empire of a solid sample in unused paint pigment form.
The Phoenicians first produced Tyrian purple in the 2nd millennium BC as an ancient civilization of the Mediterranean region originating from the coastal region of Levant. The most famous place of production is Tire – a city in Lebanon and one of the oldest continuously inhabited settlements in the world. This pigment is also produced in some other areas of Mediterranean such as North Africa.
The Tyrian purple dye sample at Carlisle was likely used to paint frescoes according to Sarah Irving, a spokeswoman for Cumberland Council which collaborated with Wardell Armstrong on