It's some Wister Gokubito. I don't know either. But that's what it says! It's a nice multi yarn, three ply with each ply a different shade. It's worsted weight, 75 meters to 150 grams, and I think it's machine washable with cold water. Not 100% sure there. I did try to felt a piece and while it kind of did, I was still able to easily pull the strand back apart after vigorously trying to felt it. The Wool of the Andes (Knit Picks) felted easily with less agitation. At this point, I've finished both pairs of socks, but have only uploaded the photographs of the first pair:
Yup, another pair of Thujas. It's my go-to pattern. Fast, easy, and who doesn't like a nice warm pair of socks in the winter? Especially when they're handmade!
Pattern: Thuja from Knitty
Yarn: Japanese yarn, Wister Gokubito
Timeframe: Bought the yarn on a Friday, cast on Saturday, finished and gifted it the following Wednesday.
Mods: None, 9.5" foot
Problems: None. Love this pattern!