Thesethreads are copper wire wrapped with filament silk and then coiled over a mandrel into a purl. They are couched in place with matching silk threads, such as Au Ver a Soie 100/3 or Soie Paris. The purls can be couched down as seen to outline and fill figures. They can also be stretched and used to form hair for lions or people in stumpwork. Often they are cut into shorter pieces and threaded onto silk to be sewn in place, forming loops which stick up off the fabric. Entire flowers were filled using this technique.
Individual colors are sold that match the Cabinet of Curiosities Historic Colors. Note that garnet color can work as the dark value for both the flame and redde families.