Tonoko: Iron Ochre Pulverized for Japanese Lacquer Groundwork (after Rein 1889)

Japanese lacquerers build a hard ground under the lacquer from a powder they call to-no-ko. Rein, who studied the workshops in the 1870s, names it plainly: iron ochre powder. Stirred with water to a stiff paste and tempered with raw lacquer, it becomes the kiri-ko and sabi grounds, and the sabi putty of kintsugi. Result: tonoko, iron ochre ground to a fine powder. Source: J. J. Rein, The Industries of Japan (1889), pp. 354 and 358. Rein says only 'pulverized'; mortar and sieve are ours. Picture drawn by Youblob.