Summary Pierre-Joseph Macquer (1718–1784) is well known as one of the major chemists in the eighteenth century as a theoretician and a teacher. He is also known for his works on dyeing. This paper presents a new face of Macquer. He proposed a theory on mordants in dyeing as early as 1775. Besides his activity at the Académie des sciences, he played an important role in Government as the commissioner of dyeing from 1766 where he established close links with artisan (...) inventors. Académicien chimiste at the royal Manufactory of Sèvres from 1757, he was also the inventor of French porcelain. His notebooks show his organization, method, courage, passion and obstinacy in the search for the paste for hard porcelain. He also proposed an interpretation of its formation. Macquer was both a theoretician and a practical expert in dyeing as well as in porcelain making. He managed to bridge the gap between science and art. (shrink)