No doubt they were made from otter-seal skin which is shown to be brown. And the South Pole is not exactly a plant-friendly environment…I’ll just assume the Northern Water Tribe trades with the Earth Kingdom, but the Southern Tribe is shown to be tiny and isolated. On another note, I have never heard international trade being mentioned on Avatar except once, and that was a lie. • Well, with all the weird wildlife in the ATLA world, maybe there’s some kind of animal at the poles that makes ink. I don’t know if real ink-making animals make really dark blue ink or black ink, but this is ATLA, so it’s possible. • Squid in Real Life make really dark ink. Maybe their [Insert Animal]-Squids just have really dark blue/purple ink that the Water Tribes just dilute to make different shades. Makes as much sense as, say, a Giant eyeless Mole thing that literally sees through smell. • The Gaang meets an Earth Kingdom merchant who recognizes and readily accepts their Water Tribe currency, so clearl