"For centuries- silk has been the traditional beading material in necklace manufacturing. Pure natural silk feels incredibly soft and smooth. Silk threads have good tensile strength and little stretch- which make them the ideal choice for many works and knotting. Necklaces made with natural silk drape naturally along the contours of the body and always project a look of elegance and beauty. GRIFFIN 100% Natural Silk only ever originates from the high-quality center (filament silk) of the silk cocoon thread and is twisted three times. Only this sleek thread has the characteristic luster and the irresistible natural beauty of pure natural silk.

I recommend using silk cord if your project is all real pearls or mostly real pearls.   I recommend nylon cord if your project has no real pearls Silk naturally deteriorates every 3-5 years, so things done on silk have to be restrung frequently.   You do not have that problem with nylon. However, Nylon ruins pearls.   Most bead stringing and hand knotting materials have some nylon base.    Nylon cuts into the pearl at the hole, beginning with chips around the hole, then layers of the pearl nacre coming off. Also store real pearls in bags made of natural material (silk, cotton) and keep these stored out of the sun and out of the air.   This will considerably lengthen the time the silk will maintain its integrity. [Storing real pearls in plastic bags also ruins the pearls.   Bad chemical interaction.]

If using glue on the knots with silk cord, I suggest using G-S Hypo FABRIC Cement or any Fabric Tacky glue.     Don't use superglue.   Most glues do not work well with silk.     With nylon I prefer to use a jeweler's glue like Beacon 527 or E6000.