The World’s Oldest Artificial Pigment

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The world’s oldest artificial pigment, Egyptian Blue, was first used over 4,500 years ago. It was apparently first formulated in Egypt, but was used by Greeks and other contemporary cultures as well. And now some of its unique properties are finding potential applications in today’s world.

The creation of Egyptian Blue involved a complex chemical process. It is a mixture of silica, copper, lime and natron, and had to be heated at least once during its formulation. Its blue coloring is caused by the presence of a calcium-copper tetrasilicate which is also found as a natural mineral called cuprorivaite. The Egyptians called it hsbd-iryt, which means artificial lapis lazuli.

The Egyptians loved bright colors and applied Egyptian Blue to numerous objects. They used it on stone, wood, papyrus, plaster and canvas and included it as a coloring agent when they made beads, scarabs, cylinder seals, pots, statuettes and numerous other products. It has been found on wall paintings at Luxor and on sculptures recovered at the Parthenon. It was used by artisans in the Near East and the Eastern Mediterranean, and appeared throughout the Roman Empire until the end of the Fourth Century AD.

When a red light is shone on the Egyptian Blue pigment, it reflects infrared light which is easily detected by night-vision goggles or cameras. Archaeologists and other experts have taken advantage of this unusual property to help identify genuine antiquities since the pigment was not used after the 4^th century AD. It appears that the secret to its manufacture was lost about that time. Sir Humphry Davy and other 19^th-century scientists began studying Egyptian Blue and now it is the subject of investigation by chemists at the University of Georgia. Those same researchers are not looking at a related compound, barium copper tetrasilicate, which was used as a pigment by the ancient Chinese.

The University of Georgia team of chemists is excited about the possible modern uses of these ancient compounds. Perhaps this will encourage other researchers to investigate other ancient technologies.

If you’d like to read further, visit Archaeology’s website

You can also read my post about the potential modern-day uses of Egyptian Blue here