Copper Stone-set Striped Spacer

The least conspicuous piece is often the most useful. This is a thin ring, ribbed on both faces, the ribs running from the hole all the way to the rim. The relief is shallow: a fingertip can feel it, while the eye needs a raking angle to see it. The edge is chamfered all round, so it does not cut the cord. A ring of small stones is set at the centre, their tables sitting a little above the copper. The disc is barely thicker than a sheet of paper, and in the hand you hardly feel it at all.

A disc is the least conspicuous thing on a string and its work is entirely practical. Two beads sitting against each other grind mouth against mouth, and after a year of that the hole chips out. Add a disc and it is the disc that wears, while the beads survive. A metal disc is harder than leather or coconut shell, so the protection is more complete; the price is a little extra weight and a faint sound. The sound is fine, audible when you walk and especially noticeable in a quiet room.

Ribbing is not difficult on metal; making it even is the difficulty. Push the pattern round and round and the least difference in pressure leaves the spacing uneven, which raking light then exposes completely. Good ribbing is equidistant from every angle and ripples like water as the piece turns. It is also the quickest way to judge the work. Copper's hardness shows directly in the ribs, and harder copper holds a crisper line.

Its diameter usually sits close to that of the main bead, so it disappears in the middle and shows only a thread of brightness at the side. People who prefer restraint choose this sort: nothing appears to have been added to the string, yet the beads are no longer grinding. The ring of stones is the only ornament, a fine bright line under light that a careless glance takes for a reflection. The stones are white zircon, on the cool side, separated from the warm brass by a layer of metal.

A thin disc distorts, so do not hold it with pliers and force it onto the cord; push it on with a finger. To clean it, lay it flat in the palm and brush both faces with a soft brush and clean water, then dry it at once, since water left in the rib grooves leaves marks. Over time a dark film gathers in the ribs. That is normal; do not attack it with toothpaste, which dulls the copper surface. If you store several stacked together, put a sheet of soft paper between them so they do not rub.