Thursday, July 14, 2011

Prussian Blue

In the workshops we were encouraged to become familiar with our pigments. I'm developing my pigment properties template based on Koo's work. Mine is still a work in progress and while the template develops I'll be building data on my pigments and creating documents for the web. As this project comes together I will be posting out to my soon to come new web site.

Here's my first pigment property sheet:

Common Name: Prussian Blue

Alternate Names: Milori blue, Iron blue, Turnbulls Blue

Color Index: PB27 77510

Composition: C18Fe7N18

Synthetic Inorganic

Supplier: Kremer (45200) $7.80/100g

Toxicity: Nontoxic

Particle Size: .5 micron

Warm/cool: neutral

Saturation: medium

Specific gravity: 1.8 (1.7 Nat Pig)

Refractive Index: 1.56-1.662

Semi transparent

Lightfast (should test)

Disperses well (no dispersant needed) Mix to a thick state as further mixing leads to a wetter mix.

Engineer's blue and the pigment formed on cyanotypes - giving them their common name blueprints. Certain crayons were once colored with Prussian blue (later relabeled Midnight Blue). It is also a popular pigment in paints. Similarly, Prussian blue is the basis for laundry bluing.

Prussian blue in oil paint is the traditional material used for spotting metal surfaces such as surface plates and bearings for hand scraping. A thin layer of non-drying paste is applied to a reference surface and transfers to the low spots of the workpiece. The toolmaker then scrapes, stones, or otherwise removes the unmarked high spots. Prussian blue is preferable because it will not abrade the extremely precise reference surfaces as many ground pigments may.

Prussian blue was first produced as a blue dye in 1704 and has been used by artists and manufacturers ever since. It got its name from its use as a dye for Prussian military uniforms. Prussian blue dye and paint are still available today from art supply stores.

Since the 1960s, Prussian blue has been used to treat people who have been internally contaminated with radioactive cesium (mainly Cs-137) and nonradioactive thallium (once an ingredient in rat poisons). Doctors can prescribe Prussian blue at any point after they have determined that a person who is internally contaminated would benefit from treatment. Prussian blue will help speed up the removal of cesium and thallium from the body.


  1. Wow John! Fascinating stuff! I have collected antique and vintage photographs for years and have quite a fair number of cyanotypes- it never dawned on me that they share a link with common architects' blueprints. Wonderful info here- thanks so much for sharing!
    ~ gretchen

  2. Glad you enjoyed this, Gretchen. I will over time collecting data on all my pigments. This information was from the web. I still need to hit my books and see if there might be more.