Shinshu tsumugi is a type of silk fabric also known as pongee and produced throughout Nagano prefecture. Each region in the prefecture has their own production styles and techniques. This craft is known for superb color dyeing and quietly restrained silk sheen. The raw materials are hand-spun threads from raw silk, wild silk, dupioni silk, and floss silk.
For more detailed information including a description, history, and the general production process, please see the Kogei Japan: Traditional Crafts of Japan website.