This beanie is made with the Herringbone Half Double Crochet stitch. I haven’t tried that stitch yet, but it looks great. The beanie is made with super bulky yarn, which contains 85% Acrylic and 15% nylon. The pattern is available in 3 sizes.
You can find the free crochet pattern of the Kids Cobblestone Beanie on the website of Sweet Everly B.