Hi, Melanie, Could I ask what is the usage of your versus knotting? For bracelet or necklace or something not for wearing? If I know it, it would be better to chose the right cord. I have ever used cotton yarn, it would be Ok, as for embroidery, I haven't used it yet, but guess you can have a try on it, perhaps it is a good chose as well. Some website such as Fire Mountain, Pandahall, Artbeads and so on all can have the string & thread materials for your beading works. Hope you would have great fun in beading projects.