This is the fine coiled spring of wire called French wire, bullion, gimp or purl (!). It is used to reinforce and protect the silk where the strung pearls are attached to the clasp. This is 1.5mm diameter. The length is 45 cm which will be enough for about 30 necklaces (phew!) . It gives the most professional finish to any pearl necklace. Supplied in a small plastic case necessary to protect this most fragile finding.

A bright wire is one with what looks like a diamond cut effect, so it has facets which sparkle

We recommend that you cut up the whole length as soon as you receive it, as this stuff will kink, bend, stretch, squash and generally distort if you so much as look at it the wrong way.
Use fine nail or embroidery scissors or snips