If you prefer silk, we think Griffin 100% Natural Silk Bead Cord #10 works best for knotting Mala Necklaces, but #8 will do in a pinch.  Our colorful .5mm nylon cord on 7 meter spools is also a great option for knotting your Mala or prayer jewelry. We have also fallen in love with waxed polyester cord for knotting. It's silky smooth and holds up really well over time.