Twisted rope is the name that was given to this string. It's a string that is fairly simple but I love what you can do with it. And there are several variations too. You can see the basic string at Margaret Bremer's blog by clicking here.
Here I used it twice. Once in a traditional black and white and then again with color. The colored one was done using Derwent Intense colored pencils with a watercolor technique. I did the color first so I could focus on the highlights. Then I added the tangles with penwork, purposely skipping the highlight area to add some sparkles.