The gorgeous rose pink used in many mediæval manuscripts comes from the root of the madder plant – rubia tinctorum. In my copy of the miniature David as a psalmist from the Westminster Psalter (see right), it is used both for David’s thick and luxurious ermine-lined cloak as well as the background to the border. David wearing a pink cloak isn’t quite what might be expected, but it was a popular colour in the Middle Ages.
Madder was used mainly as a dye in ancient times. There is cloth dyed with madder in the tomb of Tutankhamun and also evidence of its use to around 1500 BC, However, Raman spectroscopy has shown that its use extends even further back. A leather quiver dating back to 4,000 BC was also found to have been dyed with madder.
The madder plant itself is not particularly spectacular. It is from the same family as coffee and the plants grow to about 60–100 cm high. Small yellow flowers appear at the end of June and dark grey or black berries develop by the end of September. The whole plant dies down in the winter and looks like straw. The roots which produce the colour are harvested after 3 years, although the best colour comes from roots of plants at least 5 years old, when the roots are pencil-thick. Even older plants have much thicker roots and those about 15 years old have roots 2–3 cm thick.
Once the soil has been removed the roots are cut into short strips. The centre of the roots are yellow when fresh but turn red on exposure to air. Fresh roots produce a more orange colour, and dried roots more red. The roots are soaked for 24 hours and then pulverised and soaked more which releases the colour.
In mediæval times small pieces of cloth (clothlets) would be soaked in the coloured liquid which they absorbed, and then allowed to dry. The pigment could then be transported easily. When it was needed, the clothlets were soaked again to reconstitute the coloured liquid and this mixed with an adhesive such as egg or gum Arabic to make usable paint.
Early on Spain produced most madder but by the 13th century it was cultivated all over Europe. It is said to grow best in chalky soil, yet it did well also in the sandy soils of the Netherlands. Madder has always been expensive and by 1860, the UK imported £1.25 million-worth of madder each year. In 1804 the colourist George Field changed the method of extracting the dye which made it more productive, and his work was acquired by William Winsor of Winsor and Newton.
In the 19th century alizarin, a dye derived from madder, was synthesised making the colour not so expensive but it doesn’t have the softness and translucence of the beautiful madder as in the manuscript on the right.