A painted swatch of Van Dyke brown:

Brief description of Van Dyke brown:
It's a transparent brown natural earth containing usually over 90% of organic matter. Derived from earth compounds such as soil and peat and positively identified in paintings since 17th century, was extensively used in the 19th Century in both oils and water colour. This color is found in the pictures of the old masters, among them Rubens, who used it mixed with gold ochre as a warm, transparent brown, which held up particularly well in resin varnish.
Names for Van Dyke brown:
| Pronounciation: | van dike braoon | ||||||
| Alternative names: | Cassel earth, Cologne earth | ||||||
| Non-English names: |
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| Color Index (C.I.) | PBr 8 | ||||||
| Chemical name: | Iron(III)-oxide, partly hydrated + manganese oxide partly hydrated + humic acids |
Source of Van Dyke brown:

Briquette of lignite coal for home heating use
The minerals composing Van Dyke brown, are pyrolusite and goethite, both considered to be among the most permanent pigments, and mainly lignite. Lignite, often referred to as brown coal, used as a fuel with characteristics that put it somewhere between coal and peat. Lignite is brownish-black in color and has a carbon content of around 25-35%, a high inherent moisture content sometimes as high as 66%, and an ash content ranging from 6% to 19%.
Example of use by artists:
The Van Dyke brown print process

Voigtlander pinhole, Van Dyke brown print
The Van Dyke brown print process was named for the resemblance of the print color to the brown oil paint named for the Flemish painter Van Dyck. This print method is based on the first iron-silver process, the argentotype, invented in 1842 by the English astronomer, Sir John Herschel. Both processes utilize the action of light on ferric salts and their chemistry is very similar. Vandyke brown prints are very simple and economical to make, with the sensitizer consisting of three readily available chemicals. Clearing is carried out in water and fixing is done in a weak solution of hypo.
