Blue came late among colors used in art and decoration. In ancient Greece, artists grouped colors by whether they were dark or light, instead of by their tone. The Greek word for dark blue, kyaneos, might have suggest also dark green, violet, black or brown. The word for light blue, glaukos, might have also indicate light green, grey or yellow. The Greeks imported indigo dye from India, calling it indikon. They utilized Egyptian blue in the wall paintings in Knossos, Crete Island, around 2100 BC. It was not one of the 4 primary colors for Greeks as explained by Pliny the Elder. Black, white, red, and yellow where the primary colors.
Greek Blue was utilized as a background color on the friezes in temples and to tint the beards of their statues.
Greek Blue is a warm blue without any green in it. It is a color found throughout the Mediterranean, often faded and distressed on shutters and woodwork. It has a chalky look about it yet it is a strong positive color.