Egyptian Blue is an ancient color used by artists throughout dynastic Egypt and Mesopotamia, and later integrated into the Roman Empire.
Evidence of the use of Egyptian Blue dates to end of the first dynasty, from Tomb 3121 at Saqqara. This tomb was used during the reign of Ka-sen, the last of the first dynasty pharaohs, who ruled about 2900 BC. It became widespread about 2600 BC, during the 4th dynasty, and it continued in popularity up through the Ptolemaic period.
Egyptian Blue has also been discovered outside of Egypt, in Mesopotamia at roughly the same time. Egyptian Blue beads made by Mesopotamians during the Early Dynastic III period were found at the Royal Cemetery of Ur; other examples are from Tell Brak and Tell Rimah.
Making Egyptian Blue
The principal component of Egyptian blue is calcium-copper tetrasilicate crystals, or cuprorivaite (CaCuSi4O10). The color is created in frit form (for faience) by mixing ground quartz, lime, and a copper compound with an alkali flux, and firing the mixture to between 850-1000 degrees centigrade. A concise description of the manufacture of what is believed to be Egyptian Blue is provided in the Ten Books of Architecture written by the Roman Vitruvius in the first century BC.
Methods of making blue were first discovered in Alexandria, and afterwards Vestorius set up the making of it at Puzzuoli. ... Sand and the flowers of natron are brayed together so finely that the product is like meal, and copper is grated by means of coarse files over the mixture, like sawdust, to form a conglomerate. Then it is made into balls by rolling it in the hands and thus bound together for drying. The dry balls are put in an earthern jar, and the jars in an oven. As soon as the copper and the sand grow hot and unite under the intensity of the fire, they mutually receive each other's sweat, relinquishing their peculiar qualities, and having lost their properties through the intensity of the fire, they are reduced to a blue colour. (Chapter 9, Ten Books of Architecture, translated by Morris Hicky Morgan in 1914).
Archaeological Evidence for Egyptian Blue
A manufacturing site for Egyptian Blue faience was identified and excavated at Memphis by William Flinders Petrie in the early decades of the 20th century, and re-excavated nearly a century later by Paul T. Nicholson. The site artifacts included raw materials and completed ceramic vessels using the frit. Additional manufacturing sites have been identifed at the New Kingdom site of Amarna; and unused cakes of Egyptian blue have been recovered from other New Kingdom sites such as Karnak, Thebes and Zawiyet Umm el-Rakham.
Archaeological studies of Egyptian Blue in later periods reveals that by the Roman times, a wide variety of recipes were used to create or recreate Egyptian Blue.
Sources
This glossary entry is a part of the About.com guide to Ancient Pigments, and the Dictionary of Archaeology.
Bianchetti P, Talarico F, Vigliano MG, and Ali MF. 2000. Production and characterization of Egyptian blue and Egyptian green frit. Journal of Cultural Heritage 1(2):179-188.
Hatton GD, Shortland AJ, and Tite MS. 2008. The production technology of Egyptian blue and green frits from second millennium BC Egypt and Mesopotamia. Journal of Archaeological Science 35(6):1591-1604.
Orsega EF, Agnoli F, and Mazzocchin GA. 2006. An EPR study on ancient and newly synthesised Egyptian blue. Talanta 68(3):831-835.
Pozza G, Ajò D, Chiari G, De Zuane F, and Favaro M. 2000. Photoluminescence of the inorganic pigments Egyptian blue, Han blue and Han purple. Journal of Cultural Heritage 1(4):393-398.
Vitruvius. 1st century BC (tr 1914). The Ten Books on Architecture. Translated by Morris Hicky Morgan. Harvard University Press. Published online by the Guttenberg Project in 2006.
