This is a Zip/Zipper manufactured by Stephanoise, a French company which makes lots of really lovely sewing accessories such as zips, ribbons, etc.
The zip/zipper has metal teeth and tongue which are brass-plated. The tape is brown with metallic flecks through it. The overall effect is very classy!
The zipper is in 15¾in (40cm) long, the overall width is 1 ½in (3cm), and the teeth when the zipper is closed are ¼in (0.5 cm) wide. The zipper does not open at both ends.
This item is designed to be a statement piece on the exterior of garments, but it could also be inserted if necessary. If you use it as a statement zip, it can just be stitched onto the garment (rather than inserted). This would allow the zipper to open and close as normal, but obviously there would be fabric visible behind the zipper when it was opened. This is, in effect, using the zipper as if it were braid, lace or ribbon, but it does make for a stunning look on, say, T-shirts or jackets.
Please note that this zipper has metal teeth, which makes it suitable for heavier-weight fabrics including jersey.