I recently found this very worn zanshi fabric. The warp is hemp and the weft is cotton and hemp. It has a beautiful worn feel simular to antique linen. It has been dyed with indigo, but the natural color variations in the hemp thread also lend to the design. Zanshiori is fabric that has been woven using the threads left over at the ends of numerous bobbins. due to the use of thread fragments the fabric has a random pattern and a varied texture because of the knots used to bind all the threads in the weft together. Zanshi was often woven at the end of a bolt of fabric to make use of any remaining warp.
I have listed some of this zanshi fabric for purchase here: https://www.etsy.com/listing/178807794/antique-handwoven-japanese-zanshi-indigo?ref=shop_home_active_3