Created about 5,000 years ago Egyptian blue is one of the first artificial pigments manufactured by heating a mixture of a calcium compound, sand and potash to around 850-950 C. Originally thought to have been used only in rare circumstances on important artworks. However, the discovery that 6 of the 15 Egyptian Mummy portraits and panel paintings dating from the Roman era which have been kept in storage for 100 years at the Hearst Museum have revealed traces of the rare artificial pigment has forced a re-evaluation of this belief. These works demonstrate that Egyptian blue was used for the under-drawings and for modulating colours suggesting a much wider use of the pigment than previously believed.

 

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