These are artists papers handmade from 100% long fibered cotton rag giving them exceptional strength and durability. They are tub sized (surface sized) the traditional way with gelatin. For watercolor and all drawing media. There is no chlorine or harmful chemicals used in the production of this paper- so please note that the color will vary slightly from packet to packet; from bright white to creamy natural white. In fact the run off water from the paper is pH neutral and used to irrigate an organic Mango farm in India.