J. Phys. IV France 123 (2005) 207-211
DOI: 10.1051/jp4:2005123036

Archaeological Zelliges of Meknes (14th-century): Physical measurements of the colour and identification of colouring agents

A. Ben Amara¹, A. Azzou², M. Haddad², M. Schvoerer¹, C. Ney¹, S. Ait Lyazidi² and P. Molinié<sup>3

1</sup>  Centre de Recherche en Physique Appliquée à l'Archéologie (CRPAA), Université de Bordeaux 3, CNRS, 33607 Pessac Cedex, France
²  Laboratoire de Spectronomie Physique, Faculté des Sciences, BP. 4010 Beni M'hamed, 50000 Meknes, Maroc
³  Institut des Matériaux Jean Rouxel de Nantes, 2 rue de la Houssinière, BP. 32229, 44322 Nantes Cedex 3, France

Abstract
Two series of Zelliges belonging to the Filalia and Bou-Inaniya Medersas (14th-century) in Meknes city have been studied in order to describe precisely the colour of the glazes and to identify the chromogen agents responsible for these colours. The glaze colours are physically studied by the determination of their chromatic coordinates using chromametry method. These coordinates are represented in the conventional Yxy and L*a*b* spaces. Furthermore the chromogen ions, responsible for the different colour shades, are identified by optical absorption spectrometry (OAS) and by electron paramagnetic resonance (EPR) methods. These ions are the classical ones: copper (Cu²⁺) for the green, cobalt (Co²⁺) for the blue, iron (Fe³⁺) for the honey colour and iron (Fe³⁺) in association with manganese (Mn³⁺) for the black.

© EDP Sciences 2005