Pattern in Finnish only.
The design is a heavily modified version of Spiral Hat by Pam Grushkin or Kierremyssy in Ukkolan Akat blog. The main differences are 1) open cast on, which allows grafting and leads to seamless hat; 2) short rows to form the crown and 3) i-cord brim using stitches from short rows.
The rusty hat is made of Kokon and fits most adults. The green one is made of Novita Wool and fits children or women with small head circumference.