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Preparation and application:

Henna body art is made by applying henna paste to the skin: the lawsone in the paste migrates into the outermost layer of the skin and makes a red-brown stain.

Once applied to the skin, lawsone molecules gradually migrate from the henna paste into the outer layer of the skin. Though henna's lawsone will stain the skin within minutes, the longer the paste is left on the skin, the more lawsone will migrate. Henna paste will yield as much dye as the skin can easily absorb in less than eight hours. Henna tends to crack and fall off the skin during these hours, so it is often sealed down by dabbing a sugar/lemon mix over the dried paste, or simply adding some form of sugar to the paste. This also adds to the colour of the end result, increasing the intensity of the shade.

When the paste has fallen off the skin or been removed by scraping, the stain will be orange, but should darken over the following three days to a reddish brown. Soles and palms have the thickest layer of skin and so take up the most lawsone, and take it to the greatest depth, so that hands and feet will have the darkest and most long-lasting stains. Steaming or warming the henna pattern will darken the stain, either during the time the paste is still on the skin, or after the paste has been removed. Chlorinated water and soaps may spoil the darkening process: alkaline may hasten the darkening process. After the stain reaches its peak color it will appear to fade. The henna stain is not actually fading, the skin is exfoliating: the lower, less stained cells, rise to the surface, until all stained cells are shed. 

What is henna ?

Henna (Lawsonia inermis, syn. L. alba) is a flowering plant, the sole species in the genus Lawsonia in the family Lythraceae. It is native to tropical and subtropical regions of Africa, southern Asia, and northern Australasia in semi-arid zones.

Henna is commercially cultivated in western India, Pakistan, Morocco, Yemen, Iran, Somalia, Sudan and Libya. Presently the Pali district of Rajasthan is the most heavily cultivated henna production area in India, with over 100 henna processors operating in Sojat City.

Though henna has been used for body art and hair dye since the Bronze Age, henna has had a recent renaissance in body art due to improvements in cultivation, processing, and the diasporas of people from traditional henna using regions....