Science Notes – Parsing the properties of Egyptian purple pigments

Between 30 BC and the 3rd century AD, during which period Egypt was a province of the Roman Empire, a practice developed of attaching a portrait of a mummified individual to their mummy wrappings. Approximately 1,100 of these paintings have been collected over the centuries, the majority during the 19th and early 20th century – but, as many were bought and sold as works of art instead of archaeological artefacts, information about their context and provenance has disappeared.