The world's rarest textile

This week a rare sea silk hat was due to be auctioned in New York.

Byssus Silk is harvested from the noble pen shell Pinna nobilis, a Mediterranean mollusc which is under threat from disease and parasitic infection. The silk is used by the bivalve to attach itself to rocks and is collected by divers who harvest it and prepare it for spinning. You can read more about the material on a 2015 blog entry here.    

Pieces made from byssus are extremely rare. The hat comes from a private collection in Croatia and this was the first time it has been viewed in public. Have a look at the Guardian article, kindly sent in by a reader, and at this piece to see what else was offered at this auction.