Bolt Threads, along with Germany’s AMSilk and Japan’s Spiber all develops "spider-silk", a type of silk fiber without the help of any spiders. It is a protein brewed with genetically engineered yeast and then spun into fibers. The fibers can be spin into yarn and then woven/knitted into a fabric. Stella McCartney works with Bolt Threads and have already developed some garments with spider silk.

bergstrand material GUIDE ranking*

The materials is not yet available for fashion brands.


Ranking of this material is highly dependent on the sourcing. If considering using this material, we strongly recommend performing due diligence of suppliers and performing inspections of the supply chain.
* The Bergstrand Material Guide Ranking is only a guide. Our consultants can help with accurate assessments of your brand’s use of materials.
Photography credit:
Bolt Threads

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