100g Potassium Ferricyanide + 250g Ferric Ammonium Citrate Chemicals for creating cyanotypes prints. Cyanotype is a slow-reacting, economical photographic printing light-sensitive formulation, and it produces cyan-blue prints. The process used in this kit involves two chemicals - ferric ammonium citrate and potassium ferricyanide - and only water to develop and fix. You can view the instructions here (pdf). Prior to using these chemicals, please read the safety data sheets: Potassium Ferricyanide - safety data sheet (pdf)Hazard statements: EUH032: Contact with acids liberates very toxic gas. Ferric Ammonium Citrate - safety data sheet (pdf)Potential Acute Health Effects: Slightly hazardous in case of skin contact (irritant), eye contact (irritant), ingestion, and inhalation.