German technology
Humic Substances Based Products
Humintech GmbH
Am Pösenberg 9-13
D-41517 Grevenbroich

Telefon: +49 2181 70 676 - 0
Fax: +49 2181 70 676 - 22
E-Mail senden


Van Dyke brown, also known as Cassel earth and Cologne earth, is a brown earth containing iron and manganese oxides and lignites, which are organic substances from peat or coal. It was first used in European painting in the 17th century and is still in use today. This color is found in the pictures of the old masters, Rembrant, among them Rubens, who used it mixed with gold ochre as a warm, transparent brown, which held up particularly well in resin varnish.

Amorphous, combustible, earthy lignite of humus and humic acid, which is especially mined at Cologne earth and used as a painter's paint. The brown, fine brown coal is dried, ground and (with oil stoved). The oil consumption is quite large due to high absorption capacities. The paint slowly dries and turns gray in the light. In acids, the color is decomposed by carbon deposition; in solutions, the solution is brown in color. Colognes of the earth are translucent, they are therefore suitable for varnishing and burling. It is a very dark red brown with very translucent properties.

Cologne brown is an organic natural pigment consisting of materials found in brown coal, peat or generally in soil. Considerable confusion can be spotted in the older mentions of this pigment. It had been considered an inorganic iron pigment mainly in France and its name had also been used for various earth pigments such as umber and ochres. Its color can vary according to the thickness of the painted layer and ranges from pure black with a reddish-violet tint to grayish brown.

Pigment Names

English: Cassel brown, Cassel earth, Cassel umber, Cologne brown, Cologne earth, Cologne umber, Cullen earth, Kassel earth, Rubens brown, Van Dyck brown, Van Dyke brown, Vandyke brown.

French: Terre de Cassel, Terre de Cologne

German: Kasslerbraun, Kasseler Erde, Kölnische Erde, Van Dyck Braun

Italian: Terra di Cassel, Terra di Colonia

Spanish: Tierra de Cassel, carmelita Van Dyck  


Humintech is a biotech company based in Grevenbroich, Germany. We are primarily focused on the research, development and industrial production of humic matter and humic acids for the agricultural sector. Our products find further use in pharmaceutical, construction industry, for ecological purposes such as water purification and soil decontamination.


Humintech GmbH

Am Pösenberg 9-13
41517 Grevenbroich / Deutschland 

Phone: +49 2181 70 676 - 0
Fax: +49 2181 70 676 - 22


Job offers

Cookie Notice In order to optimize our website for you and to continuously improve it, we use cookies. By continuing to use the website, you consent to the use of cookies. Further information on cookies can be found in our Privacy Policy. Below you can set which kind of services & cookies you want to allow.
Accept All
Accept only essential Cookies
Cookie Settings Here you can toggle different kinds of cookies to your liking.
Accept All