Coxswains waxed string. Grooves in a wax block preserved like scratches down a back. The sort of string you wouldn't squander. I have a clatter of shells from a County Down beach with the tops knocked off. Like ossified calamari. I thread a few on my ring finger and they clink nicely. They'll make good wind chimes for the back door, I think. I have the string for that job.