Hikihaku is a traditional weaving technique using metallic threads. Precious metals such as gold, silver, and platinum are pounded into a paper-thin metal leaf, and combined with paper coated in lacquer. This is then cut by hand into fine yarns.
(Photo credit: web.kyoto-inet.or.jp)
The gold foil－pasted paper is cut into 100 threads per sun, or 3.8 cm, which are woven weft-wise into the fabric to create the sanju tateyasura weave structure that enhances the effect of Hikihaku. As the Hikihaku yarns are very stiff, this technique is usually only used for ceremonial Obi belts, for things like weddings.
For dyeing, a gold-containing dye with excellent color fastness to light is used to produce colorful but subdued tones.