Indigo Printing @museum.de

M: When the first merchant ships brought indigo back from the colonies, it gave Europeans their first experience of a true blue dye. Previously, a relatively pale blue had been achieved by using woad. But when indigo arrived from East Asia in around 1600, it became possible to dye textiles a deep, luminous blue. An elaborate process even allowed the fabrics to be decorated and printed with patterns.

F: Indigo printing involved carving the patterns into large wooden blocks, which were then applied to the cloth. The blocks were dipped in a wax-like substance, pressed on to the white linen and carefully tapped. To ensure that regular repeats of the pattern were achieved, the blocks featured little marks showing where to apply them next. When the pattern block had been applied to an entire length of cloth, the textile went into an indigo dye bath.

M: Suspended from special frames, the fabrics were carefully lowered into the dye bath – but the dye wasn't absorbed by the fibres that had previously been printed and sealed by the wax. The remaining fabric was thoroughly soaked in the liquid. When the cloth was hauled out, the immediate response was "how disappointing" – instead of bright blue, it had turned a dirty yellowish green. But repeating the process several times and a chemical reaction with the oxygen in the air finally allowed the deep blue to emerge.

F: Once the dyeing process was over, the waxy layer had to be stripped out with diluted acids. As soon as the acids had done their work, the white patterns emerged gleaming against the deep blue background. A minor – blue – miracle indeed!