Potassium Ferricyanide is a red salt that is used with
Ferric Ammonium Citrate for cyanotype.
4 oz/113.40 g (CHM0101)
8 oz/0.23 kg (CHM1101)
1 lb/0.45 kg (CHM2101) pictured
Ferric Ammonium Citrate
Ferric Ammonium Citrate is a light-sensitive iron salt that is used with
Potassium Ferricyanide for cyanotype.
8 oz/.23 kg (CHM1102)
1 lb/0.45 kg (CHM2102) pictured
Any natural surface, including cotton, linen, silk, canvas, wool, paper, wood and leather.
Add 40 grams (approximately 2 tablespoons) Potassium Ferricyanide to 400 ml (1.7 cups) water to create Stock Solution A. Add 100 grams (approximately .5 cup) Ferric Ammonium Citrate to 400 ml (1.7 cups) water to create Stock Solution B. Allow to fully dissolve over 24 hours. Stock solutions have long shelf lives and should be stored in a cool, dark place.
Mix Stock Solutions A & B in equal parts to create the cyanotype sensitizer. Mix only the amount you immediately need, as the sensitizer is stable just 2-4 hours. Coat paper or fabric with the sensitizer and allow to dry in the dark. Once dry, make exposures in sunlight (1-30 minutes, depending on conditions) or under a UV light source, placing objects or a film negative on the coated surface to create an image. (Note: over-exposure is generally preferred to under-exposure. The print should look bronze in color after an adequate exposure). Process prints in a tray of cold water. Wash for at least 5 minutes and allow to air dry. During washing and drying, cyanotypes will oxidize to their final, deep blue color. To instantly oxidize the print to its final color, submerge in a dilute bath of hydrogen peroxide after washing, then rinse and dry.
*The chemicals used for cyanotype are inexpensive and go a long way. Despite their perhaps alarming names, both are safe to handle and mix. That said, care should be taken to avoid ingestion, inhalation and contact with skin.