Solid colors are crafted from 100% Cotton. Heather Grey is made from 90% Cotton and 10% Polyester. Dark Heather and Heather Blue consist of 50% Cotton and 50% Polyester. Dark Heather, Heather Blue, and all other Heathers contain 65% Polyester and 35% Cotton. Girls' Heathers are composed of 60% Cotton and 40% Polyester.