Discovery of copper chloride cancer in ancient Egyptian polychromic wall paintings and faience: A developing archaeological disaster

On the stability of mediaeval inorganic pigments: a literature review of the effect of climate, material selection, biological activity, analysis and conservation treatments

“…Unstable, blackening upon light exposure [1,64] Involved in discolouration [93,245] Whitening [68, 93, Green discolouration [156][157][158] Green discolouration [156][157][158] - [28] - [28] Black …”

“…ions are leached and react with Cl − ions from the glass itself or from circulating solutions to form carbonates and chlorides [156][157][158]. Degraded Egyptian blue was found to contain chlorides (atacamite and eriochalcite CuCl 2 ·2H 2 O) [158].…”

Examination of some pigments, grounds and media from Egyptian cartonnage fragments in the Petrie Museum, University College London

“…ground lapis lazuli, (Na,Ca) 8 (AlSiO 4 ) 6 (SO 4 ,S,Cl) 2 ) was used remains unclear (Heywood, 2001a;Scott, in press). Egyptian green, is also liable to be degraded to another green-coloured basic copper chloride (Schiegl et al, 1989;Lee and Quirke, 2000).…”

“…This is not necessarily the case for green pigments, where there are a number of problems relating to their characterization, some of which have been described by Scott (in press). In summary, these difficulties relate to the subtleties of pigment characterization, use of organometallic compounds of copper, such as copper-proteinate, copper-carbohydrate and copper-wax pigments (Scott, 2002;Scott et al, 2003Scott et al, , 2004Daniels, 2007), alteration of the original green pigment to another green-coloured product, and alteration of blue pigments, such as Egyptian blue, to a degraded green colour (Lee and Quirke, 2000;Scott, in press;Schiegl et al, 1989Schiegl et al, , 1992.…”

Flux growth and characterization of cuprorivaite: the influence of temperature, flux, and silica source

“…So far, many works dealt with a detailed study of the Egyptian blue (i.e., cuprorivaite) found in different manufactures in order to gain a deep insight into the microchemical structure and to get information about the manufacturing process and sources of starting materials [5][6][7][8]. Analysis of some original samples [9,10] showed that the Egyptian blue is constituted mainly of cuprorivaite, a calcium-copper tetrasilicate with the formula CaCuSi 4 O 10 , mixed with silica phase, Cu-doped wollastonite, cuprite, or tenorite depending on the presence of excess of lime and copper ingredients respectively. Moreover, starting from the end of the nineteenth century to beginning of the twentieth century, many researchers began to synthesize these pigments [11,12], investigating some factors involved in their process of formation.…”