Cyanotype paper
Photographic printing medium that produces cyan-blue prints through a chemical process involving ferric ammonium citrate and potassium ferricyanide. The paper is coated with these chemicals, exposed to UV light, and then washed to reveal the final image, making it a simple and low-cost method for creating copies of drawings and artistic prints. Cyanotype paper is popular among artists, educators, and hobbyists for its unique visual effects and ease of use.