Grecian curls (pattern)
A blackwork pattern made up of adjoining groups of ‘G’ shapes. It is a very open, larger scale pattern and is suitable for creating a graphic effect.
Further Reading

Method
Start with a horizontal stitch over two threads, then a vertical stitch, also over two threads, both touching on the lower right hand side to form a backwards L-shape.
Work three larger stitches over four threads of the fabric, each touching the last, creating a shape that spirals out from the centre
Stitch a horizontal stitch and a vertical stitch to connect the next shape.(Both over two threads)
A mirror image of the G shape is then worked below, leaving a space of two threads between them.
Work vertically down the area, using a series of straight and back stitches to follow the design and create the pattern in stitch.
Work back up the area with a second column which forms a mirror image to the previous column.
Continue to fill the area.

Structure of stitch
Embroidery Techniques
References
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Various Authors, The Royal School of Needlework Book of Embroidery (2018) , p.145
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Becky Hogg, RSN Essential Stitch Guides: Blackwork (2010) , p.51