. . . . "Egyptian Blue"@es . . . "white"@es . . "42"^^ . "color"@es . . . . . "Egyptian blue is chemically known as calcium copper silicate (CaCuSi4O10 or CaO\u00B7CuO\u00B74SiO2). It is a pigment used by Egyptians for thousands of years. It is considered to be the first synthetic pigment. The pigment was known to the Romans by the name caeruleum. Vitruvius describes in his work de architectura how it was produced by grinding sand, copper and natron and heating the mixture, shaped into small balls, in a furnace. Lime is necessary for the production as well, but probably lime-rich sand was used. After the Roman era, Egyptian Blue fell from usage and the manner of its creation forgotten. The ancient Egyptian word wedjet signifies blue, and the same word is used for the human eye, as in the Eye of Ra."@es . . . "Egyptian blue"@es . "77"^^ . . . . . "244"^^ . "52"^^ . "166"^^ . "1034"^^ . "Egyptian blue is chemically known as calcium copper silicate (CaCuSi4O10 or CaO\u00B7CuO\u00B74SiO2). It is a pigment used by Egyptians for thousands of years. It is considered to be the first synthetic pigment. The pigment was known to the Romans by the name caeruleum. Vitruvius describes in his work de architectura how it was produced by grinding sand, copper and natron and heating the mixture, shaped into small balls, in a furnace. Lime is necessary for the production as well, but probably lime-rich sand was used. After the Roman era, Egyptian Blue fell from usage and the manner of its creation forgotten."@es . . "16"^^ .