I spent two weeks last January in a stone workshop outside Fez, watching a man named Youssef comb pigment across a tray of carrageenan size. The colors he used were not synthetic. Vermilion ground from cinnabar, indigo carried from Gujarat, a teal made by mixing copper carbonate with a plant-based binder that he refused to name. When he laid a sheet of handmade paper onto the floating pattern and peeled it back, the result was a surface that seemed to breathe—veins of gold threading through fields of deep peacock blue, each impression entirely unrepeatable.
A Bath of Carrageenan
The technique Youssef practices is called suminagashi, a Japanese word meaning "floating ink." It arrived in Europe through Ottoman Turkey, where marblers adapted it into the peacock and nonpareil patterns that decorated fine bindings for three centuries. The tray matters enormously: too shallow and the size wrinkles; too deep and the pigment disperses into formless clouds.