Micro-Raman study of red decorations in French faiences of the 18th and 19th centuries

Obtaining the red color was a technical and economic challenge for the French faience manufactories in the 18th and 19th centuries. The tendency of the red hematite to turn into drab brown during the firing process explains the difficulty in obtaining this color. Red decorations in shards coming from the four production centers of faience manufacturing during this period—Rouen (northwest), Nevers (central), Thiviers (southwest) and Argonne (northeast)—have been studied by means of micro-Raman spectroscopy, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Among them, Thiviers appears to be the leader thanks to a particular reddish sandstone called ‘Gres de T…