Egyptian blue

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How Egyptian blue is made:

Origin: artificial identical with the mineral cuprorivaite (at Mineralogy Database)
King Ramses III. (1170 B.C.) The blue helmet with golden serpent is the symbol of royalty
Artificial variety of pigment Heating a mixture of a calcium compound (carbonate, sulfate or hydroxide), copper compound (oxide or malachite) and quartz or silica gel in proportions that correspond to a ratio of 4 SiO2 : 1 CaO : 1 CuO to a temperature of 900°C using a flux of sodium carbonate, potassium carbonate or borax. The mixture is then maintained at a temperature of 800°C for a period ranging from 10 to 100 hours.

The ground pigment:

Pile of ground Egyptian blue