Double Strand Loop Guilloche (opposing directions). Finished piece before grouting.
This didn't turn out too well due the reduced width of some of the strands which I've hopefully remedied for future mosaics by slightly changing the marks on the staff.
It's tempting to redo mosaics that aren't turning out exactly as you want them but I always feel it's better to finish them as they are as they become part of your 'textbooks'. Mosaics you can look back on and see exactly how the problems begin.