Cap and barrel are made of ebonite lacquerd with Wajima urushi. Japanese would describe light colors with the term "Arai", and the deep red is called "shu", so "arai-shu" means the most brilliant and lightest of urushi colors.
I found Iguana really friendly, helpful and efficient to both buy the pen and when I had a query - very quick to respond. The pen is gorgeous and I’m now using it every day.