This is a light weight, mostly cotton lumpy knit slouchy style hat that should fit most sizes.  It's got lots of room in the body of the hat and tapers nicely to a close fit around the face, where the cotton is very gentle on the skin.  The solid color purplish sections are organic cotton.  The green is a special yarn that I bought from my friends at Joybilee Farm in Canada.  It's a cotton/silk four ply blend in shades of green and navy blue with small 'rosette' coils.  Four ply is hard enough to make, but with the rosettes, too, this is some very nice yarn that I've been saving for awhile for just the right project.  The other lumpy sections are various blends of cotton and silk with some wool, lots of coils, and dark pink mohair curls for an added touch that really sets this hat off beautifully.