Last month I bought a 2000X endoscope camera to look more closely at my Silk strings. I find it very interesting to compare some of the fibers from different sources. To the left is a Chinese Bombyx Mori silk that was originally 3-plied and approximately .002 mm.
The fibers are said to be 7.84 microns more or less. (A micron is .000785 mm) A 1680 thread would come to about 10.34 mm, and we know this to not be the case. In fact, the way the fibers pack together is partly affected by their pentagonal shape.
Here is a small section of a set of wrapped strings. They are very neatly packed, while you can see the plies in the wrapping.
Here you can see a few stray fibers, too, that give a sense of scale to the wrapping.
This is what, until the addition of the 2000x endoscopic camera view I was able to offer as a closeup of my strings.
A closer look at burnished strings at .62 mm. These are of a wild silk, called Tussah, from Saturniid moths (see Antheraea paphia). I prefer this silk for Lyre strings.
Tussah is stronger than silk from Bombyx mori, the more standard silk for garments and Damask weaving. Tussah is a little creamier in tone and sometimes varies a bit in thread diameter so creating specific gauges is a little trickier. It does, however, look a little more “authentic” to some people when strung on instruments of antiquity.
You can see that the surface has been burnished to make them much smoother than they would be otherwise.
These are .62 mm:
Real Silk strings can be purchased in my Etsy store