Sean Bradley, Staff Writer 

On Friday, Nov. 15, I had the pleasure of attending an event hosted by the Chymian Society and Greenhouse Club where students got to make cyanotypes from objects in nature. In this special edition of “Nature at La Salle,” we’ll learn more about cyanotypes and the cool process behind how they’re made.

A cyanotype is a camera-less photographic technique that involves laying an object on paper that is coated with a solution of photoactive chemicals, exposing those chemicals to ultraviolet (UV) light to allow them to react and washing the paper with water to create Prussian blue and white images.

The process of making cyanotypes was first discovered in 1842 by English polymath Sir John Herschel, who exposed paper that was coated with iron salts solution to sunlight and washed with water. After its invention, Herschel started using cyanotype printing to make “blueprints” of his notes and diagrams. The following year, 1843, Anna Atkins, an English botanist, photographer and friend of Herschel, produced and published the first photographic illustrated book, “Photographs of British Algae: Cyanotype Impressions.” Between 1843 and 1853 she produced a total of three volumes in the series.

At the event, students got to collect objects from nature from La Salle’s campus, including leaves, flowers and stems to make their own cyanotypes. Once the objects were collected, students then made their own cool cyanotype designs. Dr. Denise Femia, a chemistry professor at La Salle and an organizer for the event, was kind to provide insight on the cyanotype process. She explained that a solution containing the chemicals, ferric ammonium citrate and potassium ferricyanide, was kept in the dark. The solution was then brushed onto paper and left to dry in the dark.

After drying the paper, objects (in this case leaves) were placed onto the paper. For the sake of time, pre-treated paper from a cyanotype kit was used at the event. A sheet of transparent paper was also used and placed over the leaves on the paper to create a better image. After creating the setup, the leaves on the paper were exposed to UV light, which gave the chemicals energy and caused them to react. 

The product from this reaction was Prussian blue, which is a solid-state material meaning it has a repeating crystal structure consisting of positively charged iron ions and negatively charged cyanides. In the case of the event, the objects were exposed to UV light for 5 minutes in the dark using UV flashlights, which resulted in reversed prints. Lastly, the prints were rinsed in water for a minute to wash off any solution, resulting in a stunning print where exposed areas are Prussian blue and unexposed areas are white.

Each student who attended got to make at least two unique cyanotype designs. Overall, it was a fun and interesting event.

For any readers interested in making their own cyanotypes at home, Dr. Femia recommends using pre-coated paper from kits for safety reasons. But overall, cyanotypes are a cool way of making art from nature and are worth learning.