Blue
Blue, one of the primary colors. Minerals such as turquoise, azurite, labradorite, and lapis lazuli are blue. Birds, fish, reptiles, insects, and other animals often have blue as their chief color. Mammals usually show this color only in their eyes and blood vessels. Many kinds of flowers and some fruits are blue.
Blue pigments and dyes used commercially are made from indigo and aniline compounds. Cobalt, iron, and copper compounds are also used to make blue pigments.
Blue has been used as the symbol of loyalty and perfection. A blue ribbon is awarded to first-prize winners in many contests. The Scottish Presbyterians of the 17th century wore blue as a symbol of their defiance of the royal red. In the symbolism of the Roman Catholic Church, blue is the color of the Virgin Mary.