S-ing (goldwork)

S-ing creates the look of a stem stitch worked in metal purl threads. Traditionally used to create stems, or veins down the centre of leaves, can also be used as an outline.
Method

Cut several small equal lengths of purl. Using a waxed double thread bring the needle and thread to the surface. Thread a purl onto the needle and gently manoeuvre it to the base of the thread. Ideally without touching it with your fingers to prevent tarnishing in the future.

Secure in position by taking the needle back down through the fabric just short of the purl length so that the purl curves slightly.

Bring the needle and thread to the surface half a purls length ahead.

Thread a second purl onto the needle and gently manoeuvre it to the base of the thread.

Secure the second purl into position by taking the needle down, halfway back under the left side of the previous purl.

Use a mellor or laying tool to gently lift the middle of the 1st purl to allow the end of the second purl to slide into position.

Repeat the sequence by bringing the needle and thread to the surface half a purls length ahead of the second stitch
Thread a third purl onto the needle and gently manoeuvre it to the base of the thread.

Secure the third purl into position by taking the needle down, halfway back under the left side of the previous purl and into the same hole as the end of the previous purl. Remember to use a mellor to gently manoeuvre it into position without cracking the purl.

Continue the sequence to create a stem stitch of metal threads.

Common uses
Traditionally used to create stems and or veins down the centre of leaves, can also be used as an outline.
Embroidery Techniques
Related Stitches
Identifying S-ing (goldwork)
S-ing can be identified as lengths of metal thread cut and attached to the fabric surface in a way that produces a rope-like appearance.
References
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Various Authors, The Royal School of Needlework Book of Embroidery (2018) , p.240
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Kate Haxell, The Stitch Bible (2012)