Green is just about the most common color in nature so finding a great green dye should be easy, right? Well, despite the fact that green leaves and plants are all around us, a beautiful green is hard to find.
Many plants yield a light celery green or yellow green with the proper mordant. (A mordant makes the dye stick to the fabric. Otherwise the dye would wash right out.) Lily of the Valley and hydrangea both give a celery green dye. But Lily of the valley is highly poisoness; roots, leaves and flowers. Queen Anne’s lace gives a pale green and foxglove an apple green. The colors are not the vibrant shades we expect. In Peru the women use leaves that they gather in the forest from the chilla (spelling?) plant. When mordanted with copper carbonate it produces a sage green, sometimes light and sometimes dark.
A word about mordants. Iron, copper, alum, lye, tin, mercury urine; just about every substnace imaginable has been used as a mordant. In the middle ages the men who dyed hats used mercury, a very poisoness heavy metal. The Mad Hatter from “Alice in Wonderland” wasn’t just a creation of Carroll’s imagination.
The other problem with natural dyes is consistency. It is difficult to use plants and achieve the same result time after time. Dyers quickly learned to cultivate dye plants as an aid to controlling the brightness of the colors. Even then, dye plants dyed in a wide range of hues. Madder, which dyed the British red coats red, dyes bright red unless it dyes pink. It is very difficult to achieve the same color over and over.
Which brings us to green. A bright emerald green was not developed until 1778. It was created by a Swedish chemist named Karl Scheele and contained arsenic. Green was a popular color for wallpaper then. (George Washington himself took time from his busy political life to plan two green rooms at Mount Vernon.) Many many people fell ill. The cause was frequently misdiagnosed since the symptoms were general and came on gradually. One theory is that arsenic may have been made into a gas by the mold living in the wallpaper paste in damp rooms. (Mmm, this sounds safe.) This dye was even used for candy for children. In 1875 the ‘Lancet’, a British medical journal, spearheaded a campaign to abolish the arsenic greens. By then the aniline dyes were being created from coal tars. These dyes created vibrant colors that were much more colorfast.
So what does this have to do with Napoleon? When imprisoned on the island of Elba, he spent much of his time in a room with the fashionable green wallpaper. When his hair was tested in modern times, it revealed a high level of arsenic. At first, it was theorized he’d been poisoned. A more recent competing theory suggested he’d been poisoned all right, by the arsenic in his wallpaper.
Natural is not always safer and while I wouldn’t use cooking utensils for my dyestuffs at least I am assured that none of them contain arsenic.