Henna, species Lawsonia intermis of the family Lythracea, is a perennial shrub that grows wild in northern Africa and southern Asia. The name henna, which comes from the Arabic word al kenna, refers to both the plant and the dye that comes from the leaves. The henna plant has narrow, grayish green leaves and small, sweet smelling clustered flowers that are white, yellow, or rose in color.
One of the oldest known hair dyes, henna is still used worldwide. The leaves are dried, pulverized, mixed with hot water, and then made into a paste. The paste is applied to the hair, and later rinsed out, leaving a reddish tint. Women in Muslim countries use henna to color their nails, hands, feet, and cheeks. In India, some brides use henna to stain a beautifully intricate design on their hands. The Berbers of North Africa believe henna represents blood and fire, and that it links humankind to nature. Henna is used in Berber marriage ceremonies because it is thought that henna has special seductive powers and that it symbolizes youth. Henna dye is used to stain leather and horses' hooves and manes. Some mummies have been found wrapped in henna-dyed cloth.
The active dye ingredient in henna is hennotannic acid, or lawsone. Henna powder is available commercially; the quality depends on where the plant was grown and what part of the plant was used to make the dye. Sometimes henna is mixed with other plant dyes, such as indigo or coffee, to obtain other hues. The henna plant also produces an aromatic oil used as perfume. Henna is now grown commercially in Morocco, China, and Australia.
See also Dyes and pigments.
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