In the Roman Empire, purple dye was an extremely valuable artificial pigment, reserved for the upper class. Producing this color was a complex process that required collecting thousands of sea snails and processing them to create just 1 gram of dye. The Tyrian purple dye block found in Carlisle, England is a rare specimen that has been identified as a solid sample of this highly prized pigment.
The process of producing Tyrian purple involved collecting and processing large quantities of carnivorous sea snails from the Mediterranean region, which may have been used for frescoes. Archaeologists and volunteers discovered the rare object during an excavation of a Roman bath in Carlisle. Newsweek reported on May 3 that analysis showed that the object contained beeswax and bromine, indicating its authenticity as a solid sample of Tyrian purple dye.
Tyrian purple was first produced by the Phoenicians in Tire, Lebanon over 2 millennia ago. This ancient civilization was known for its expertise in mining and trading activities. Although it is believed that this pigment was also produced in other areas of the Mediterranean region, including North Africa, this discovery at Carlisle is particularly unique due to its location in Northern Europe.
The Tyrian purple dye sample at Carlisle is likely to have been used to paint frescoes or adorn public buildings and homes belonging to the upper class. This pigment was so valuable that it surpassed even gold in terms of expense during Roman times. Sarah Irving, spokesperson for Cumberland Council who collaborated with Wardell Armstrong on the excavation project, confirms this use case: “This pigment can also be used to paint walls in large public buildings, homes and real estate of the upper class.”