The real story
Kintsugi, 'golden joinery', uses urushi, a lacquer made from the sap of the lacquer tree, to glue broken pottery back together; the seams are then dusted with powdered gold. It is slow work: each layer of lacquer has to harden in a warm, humid cabinet, so one repair can take weeks.
The usual origin story says the 15th-century shogun Ashikaga Yoshimasa sent a favourite cracked Chinese tea bowl to China for repair, and it came back held together with ugly metal staples. That stapled bowl, known as Bakōhan, really exists, though historians can't confirm the rest of the tale. Kintsugi grew up alongside the tea ceremony and its love of wabi-sabi, the beauty of things that are imperfect and worn.