Cyanotype is a remarkably simple process that employs two inexpensive chemicals and sunlight/UV. Prints can be made on any natural fiber: paper, cotton, silk, wool, wood, etc. The two component set magically allows you to develop prints when placed out in the sun!
The set includes two bottles, one each of Potassium Ferricyanide and Ferric Ammonium Citrate. By mixing the chemicals together in equal parts with water, you now have the cyanotype sensitizer. Coat the print material with the sensitizer and, once dry, create prints by exposing to sunlight or a UV light (3-15 minutes, depending on conditions), using objects or a film negative to create an image. After exposure, prints are processed in a tray of cool water and allowed to air dry. This set contains enough chemistry to make approximately 65 8.5" x 11" prints on paper or 50 8.5" x 11" prints on fabric, depending on the absorbency of the substrate, and instructions.
Distinctive for producing Prussian blue monochromatic prints, cyanotype was developed in the mid-19th century and quickly embraced as an inexpensive method for reproducing photographs, documents, maps and plans (hence the enduring architectural term "blueprint"). Famously, it was used by Ana Atkins and other field biologists for indexing plant specimens.