I make these hair clip/barrettes out of .045" Anodized Aluminum wire to keep them light enough that they don't pull hairs (they weigh less than 1/2 oz). The rings are a 3/16" I.D.
I start with 2 strands of Byzantine weave and connect them all along the length. I then use 8 lb. test line and tie the doubled strand onto a 3"/80mm barrette blank.