Pompeii was not grey. New research conducted by the Archaeological Park in collaboration with the University of Sannio and the Federico II University of Naples has revealed that its houses, temples, and streets were once adorned with vibrant colors. The study discovered 26 different pigments used in the decorations, presenting a new image of the city: refined, artistic, and rich in color. The investigation, which used non-invasive procedures, opens up new possibilities for the restoration and conservation of Pompeian frescoes. Among the most unexpected discoveries is an unprecedented hue of gray that was produced by a complex combination of Egyptian blue, ferrous red, and a green that was derived from barite and alunite. It is the first evidence of the use of barium sulphate in Roman art, a substance found in the Campi Flegrei and Vesuvius areas. "Understanding the composition of the pigments allows us to reconstruct the original mixtures and restore the authentic beauty of the frescoes", says Celestino Grifa, a professor at the University of Sannio. A rediscovery that transforms Pompeii into an outdoor laboratory for studying ancient art.