What makes silk strings so 'silky?'

After playing my qin, I wondered:

What exactly are these silk strings made of that made them so 'silky?'

What exactly is the wood of the qin made of that made it so 'woody?'

What gives the lacquer on the qin's fingerboard its 'lacquer-ness?'

Enjoy this video to find out more about how 'science' explains it.