Just found this short documentary on shellac production and thought others might be interested. I found the introduction music a bit intrusive, but it's soon replaced with something less distracting, so don't be put off by that early on. Warning: contains factory scenes with no trace of 'elf 'n safety! It's clear that the process remains almost unchanged for hundreds of years.
https://www.youtube.com/watch?v=lQcQ0yuekZ0
https://www.youtube.com/watch?v=lQcQ0yuekZ0