Five Fascinating Facts About Silk
Silk is exceptional as a natural fibre.
Silk is a long filament.
Silk is the only natural filament woven into fabric. Each fibre of silk is a continuous filament between 600 and 1500m in length*. That means that a single fibre of silk could as a minimum be dangled from the top of any one of the tallest buildings in the world and reach the ground (on a calm day of course) or that an athlete could run the 1500m unravelling a single strand of silk the entire length of the race.
Silk is a Protein.
Silk is a natural protein fibre. The silk bave consists of two filaments made of the protein fibroin. These are joined together by a natural gum called sericin which is removed to separate the fibroin filaments, which are known as brins.
Silk has a triangular cross-section.
Wild silk has a curved elongated cross-section, but cultivated silk (also known as Mulberry silk) has a triangular cross-section with slightly rounded corners. I studied antique silk during my Degree programme and had the privilege of access to a scanning electron microscope, so I was able to look at the amazing details for myself.
Silk filaments are very fine.
These triangular filaments are on average 15 microns in diameter (0.015 mm)** - the same cross-sectional thickness as fine cashmere. For comparison, human hair is about 5 times the thickness of a single silk filament - so no matter how fine your hair is, silk is finer still!
Silk behaves like a prism.
Because the filament is triangular in cross-section and very smooth, the entire length acts as a prism. The translucent fibre allows light to bounce around inside this prism refracting it the same way that raindrops create a rainbow. This causes the shimmering appearance that is so unique to silk.
The satin fabric that I use for my pure silk scarves has been chosen to take advantage of these exceptional qualities and give you the best shimmer from that prismatic effect of the silk’s long translucent filaments.
* Silk: Processing, Properties and Applications, K. Murugesh Babu P27
** Polymers in Biology and Medicine, D.N. Breslauer, D.L. Kaplan, in Polymer Science: A Comprehensive Reference, 2012 Volume 9, 2012, Pages 57-69