Do or dye: How humans chased colour and found it

How did we “find” colour, which shades have we lost, and how did synthetic dyes change it all? “I realised then that the answer to the fashion industry’s colour problem wasn’t going to be engineered bacterial that could poop out colour, at least not on its own,” MacDonald says, “It was going to be about changing behaviours, tightening up practices that already exist, and using materials that we’ve known for millennia.” Highlights from her findings. There are Egyptian papyri in which “instructions for making purple dye alongside advice for turning lead into gold, and pebbles into precious gems,” MacDonald writes. “But once you extract the hypobranchial gland and expose it to oxygen, it turns purple.” The hue fell out of use in the 15th century, when Pope Paul II changed the colour of his cardinals’ robes from purple to scarlet. “As soon as we could get colour from coal and later petroleum, we were not reliant on weather, farming or any of those lengthy practices any more, and we could do it faster for cheaper.” A grim brown From happy accident to grim reminder, the most sinister source of colour listed in MacDonald’s book is a rather recent abomination: ground-up Egyptian mummies, used to make a hue named Mummy Brown.