The final dilemma concerned threading the hematite beads on to the cord which caused the it to break. I inquired about the holes being made bigger and tried myself with a gimlet, but the stone is far too hard and the idea not recommended. I do like the hematite beads and really want to use them, though I recognise their limitations: their scale is possibly a little too small and maybe they are almost too close in colour and texture.
So what did I decide to do? I've taken the whole thing apart, made several lengths of cord in case of disasters and decided to include some milled old bronze-brown glass beads as additional spacers. I've placed these where I had used the circular Tyvek beads in one of my trials. They add another layer of texture which emphasises the industrial look I wanted to achieve. They also allow the long Tyvek beads to splay out, as shown in the neckline of the evening jacket photographed below. I think the combination works well. The neck piece fastens with a further milled glass bead and a loop.
I threaded 10cm of the cord through a milled glass bead and twisted it five times. I looped the cord in two and twisted it along its length. To disguise the end I then spiralled the twisted cord in the direction of the bead. The attachment is neat, secure and strong. The loop is made in a similar fashion.