I've used mine for making very thin bias strips for applique. Using my trusty ruler on fabric, cut the first edge, move the ruler over 1/4" use Hera marker to make the fold, mover ruler another 1/4" cut. The Hera marker also does the trick for sewing on silk.
PS: K roll, I'm not sure that that's a sewing tool at all but it sure is pretty and you might want to take that to a Chinese antiquities person.