Painting technique - Tanja Moderscheim

Rembrandt van Rijn, Saskia van Uylenburgh As Flora, 1641
Staatliche Kunstsammlungen Dresden – Gemäldegalerie Alte Meister
inv./cat. no. 1562; Image credit: The Rembrandt Database.

Old pigments painting blog: Vandyke Brown

(Cassel Earth, Cologne Earth)

I exclusively use pigments that were available to the 17^th century Dutch painter – something that fascinates me and also keeps me tied to my roots now I’m living abroad. I use 17th century techniques and my subject matter is a nod to the interests of that time, including heritage tulips, fruit and produce still life, and bird still life. In this old pigments painting blog you’ll read more about one of the pigments I use: Vandyke Brown, also known as Cassel Earth and Cologne Earth. It has featured on artists’ palettes since 1600 and most likely earlier.

The pigment Vandyke Brown / Cassel Earth / Cologne Earth has an interesting and centuries’ old history. It was used to create deep, dark, rich backgrounds. When we think of Dutch paintings of that time, these typical backgrounds immediately come to mind.

Old pigments, in contrast to most modern ones (meaning paint developed from the 19^th century onwards, such as synthetic ultramarine), need to be used with extra caution. Some are toxic (such as lead white and vermillion), some react with other pigments (e.g., lead white and orpiment) or painting medium, and some are fugitive / not lightfast (such as the organic lakes). There are many other things to consider, and throughout the centuries artists and craftsmen were aware of these (and if not, extensive modern research has revealed a lot!). Manuscripts and published handbooks by artists, potters and glass craftsmen have been a valuable source for artists since the mid-1500s. Some, for example “De Groote Waereld in ‘t kleen geschildert” by Willem Beurs (1692), survive today and are accessible thanks to digitisation.

Wilhelmus Beurs’s publication on painting techniques and pigments, 1692:
De groote waereld in’t kleen geschildert, of Schilderagtig tafereel van ‘s weerelds schilderyen

Without conducting a thorough literature review, some of the information for the short essay below has been lifted from manuscripts by Beurs 1692, Feller and Johnston-Feller 1997 (National Gallery of Art, Washington), Van Eikema et al. 1999 (Rijksmuseum, Amsterdam), the Pigment Database (artiscreation.com) and ColourLex (colourlex.com).

Old pigments: what is Vandyke Brown?

Vandyke Brown, now synonymous with Cassel Earth and Cologne Earth, is comprised of the humic/lignitic substances found in soil, peat and brow coal; as an ancient deposit it contains microfossils and angiosperm pollen. Chemically, iron is most abundant followed by calcium and some manganese. Throughout history the main deposits were found in the west-German regions of Cologne and Kassel (today the material is sourced from Kassel). The pigment was prepared by drying and grinding the raw material, and then mixing with linseed, walnut or poppyseed oil for oil painting. It has a beautiful, deep black-brown colour and depending on the thickness of the painted layer, can have violet undertones.

My Vandyke Brown and Cassel Earth (both NBr8)

The dry pigment. Image credit: ColourLex

Cassel / Cologne Earth is commonly thought to have been used by Anthony van Dyck (1599-1641). Born in Antwerp, Van Dyck became a leading court painter in England and is still famous today: his paintings are in major museum collections. Likely due to his fame, Cassel / Cologne Earth is also known as Vandyke Brown (with this particular spelling adopted). Interestingly, this pigment was not associated with Van Dyck until approximately 1794, more than a century after he painted.

History

Cassel / Cologne Earth is thought to have been in use since the Renaissance period and mainly in Holland and England. Unfortunately, due to the difficulty identifying organic materials using modern analytical methods, the use of this pigment can only be suspected in a number of paintings. The earliest date Cassel / Cologne Earth may have been used is during the early 1500s: an organic brown pigment was found in two paintings of 1500 to 1511 attributed to Gerard David (circa 1460-1523). Organic brown pigment was also found in paintings by Velazquez (1465-1524).

Handbooks and literature of the 17th century include recommendations for its use, confirming that it was part of painters’ palettes in that century. Karel van Mander, in his Het Schilder-Boeck (1604) recommends Cologne Earth for the shadows ‘of the flesh’ and Willem Beurs mentions Cologne Earth in his De Groote Waereld in ‘t kleen geschildert (1692).

How was Cassel / Cologne Earth used and how do I use it?

The pigment was used in oil painting, mainly as a glaze over dark areas, and in later centuries in watercolour. It was not restricted to fine art: it was used on sculptures, walls, wall and decorative papers, in woodworking and even put in snuff!

A recipe by the celebrated painter Jan Davidsz. de Heem (1606-1683/4) survives, in which he recommends a mixture of lead white, lake, bice and earth of “colon” for painting the yeast residue on grapes and other fruit:

Detail of Festoon of fruit and flowers, Jan Davidsz. de Heem
Rijksmuseum Amsterdam. Image credit: Rijksmuseum

Rubens (1577-1640) is known to have included the pigment on his palette: he mixed it with ochre, creating a warm transparent brown which ‘held up well, particularly in resin varnish’. Van Dyck was Rubens’s pupil and collaborated on a number of paintings with him, so Cassel / Cologne Earth may have entered his palette at that time.

Rembrandt van Rijn (1606-1669) used Cassel / Cologne Earth to create the dark backgrounds we know him so well for. In his painting Saskia van Uylenburgh as Flora (see below), Rembrandt used a mixture of yellow ochre, bone black, a small amount of lead white, and Cassel / Cologne Earth for the background areas. Cassel / Cologne Earth was most likely used as a glaze.

Now I’ve added Cassel Earth to my own palette, I’ve been using it in my backgrounds as well. Below is a painting of a Cornish shell; the background, a layer of Cyprus umber, was glazed with Cassel / Cologne Earth to create a deep and dark background bringing out the shell.

Rembrandt van Rijn, Saskia van Uylenburgh As Flora. Oil on oak panel, Rembrandt van Rijn, Saskia van Uylenburgh As Flora, 1641. Staatliche Kunstsammlungen Dresden, Gemäldegalerie Alte Meister. Image credit: The Rembrandt Database.
Rembrandt used Cassel Earth / Cologne Earth in a number of paintings to create rich, dark backgrounds.

Cornish Shell. I used Cassel Earth (NBr8) as a glaze over an umber background.

Centuries of confusion

Vandyke Brown has not always been synonymous with Cassel and Cologne Earth: throughout the centuries a variety of substances such as inorganic iron and earth pigments including umbers and ochres were often referred to as Vandyke Brown. These pigments were distinct from the organic, humic substance sourced from Kassel and Cologne. In France, Vandyke Brown was not considered the humic pigment but an inorganic iron oxide. Calcined (heated) ochres were also referred to as Vandyke brown at times. On the other hand, elsewhere in Europe Vandyke Brown was known as the humic pigment. Early / contemporary literature was not helpful in resolving the confusion!

The confusion between inorganic and organic-humic pigments has had consequences for the perceived permanence (lightfastness) of the pigment that is being used. True Cassel/Cologne Earth is listed as Natural Brown 8 (NBr8) in the Colour Index (1956). The organic component is vulnerable to oxidation, facilitated by light. As this results in fading, NBr8 is considered only moderately lightfast. Perhaps aware of this tendency to fade, painters in the 1600s therefore had a specific way of working with this pigment: glazing over dark areas. On the other hand, inorganic ocherous/umbrous or iron-oxide-based pigment is not subject to fading and is therefore very lightfast.

Today, due to the moderate lightfastness of NBr8, genuine NBr8 paint is sadly no longer widely available to artists, except via the fine art materials manufacturer Vasari (USA). Instead, most manufacturers use PBr8: an inorganic pigment that mainly contains manganic hydroxide and is mostly synthetic. Unfortunately, they all claim to be genuine Vandyke Brown – suggesting that the centuries’ old confusion between organic and inorganic Vandyke Brown may be alive and kicking today.One modern study on the lightfastness of NBr8 supported by The National Gallery of Art, Washington, has shown that discolouration of NBr8 may occur after an equivalent of 20-100 years exposure to museum lighting, confirming that the pigment is of intermediate light stability (Feller and Johnston-Feller, 1997). In this experiment NBr8 was glazed directly onto a bright background before exposure to light, thereby allowing more light reflection than would have been the case if NBr8 was glazed onto a dark background – the traditional 17^th century method of working with this pigment. This modern conclusion of lightfastness may therefore not reflect the fate of this pigment used in the 1600s. Unfortunately this does not change anyone’s mind and most artists don’t look further than PBr8. This is a shame as the depth of colour and magic of this early pigment, and the other old pigments, is unparalleled in modern colours.

Disasters and joy

In the abovementioned experiment the authors note that NBr8 slowly discolours from a deep brown to a golden brown, similar to areas of some paintings by for example Rembrandt. Rembrandt might not have intended this, however do we, in the 21^st century, think that this is such a disaster? Or, having most likely been aware of contemporary experience, did he intend some of his backgrounds to turn golden brown, using the pigment’s weakness to his advantage? We’ll never know.

I have proudly added NBr8 to my palette and I’m well aware of the moderate lightfastness of my NBr8 Cassel Earth. I’m using it with caution and as a glaze over dark backgrounds – the 17th century way. As with all old pigments, old manuscripts as well as modern research provide insight and therefore the power to use these colours with caution. I find that it is precisely these ‘temperamental’ characteristics that make these traditional pigments such a joy to work with. Their rich history and tradition also draws me – as if I hold a little bit of the 17^th century in my hand.

References / further reading:
Beurs 1692. De groote waereld in’t kleen geschildert, of Schilderagtig tafereel van ‘s weerelds schilderyen. Amsterdam.
ColourLex (colourlex.com).
Feller, Johnston-Feller 1997. Artists’ Pigments, A Handbook of Their History and Characteristics. National Gallery of Art, Washington.
The Pigment Database (www.artiscreation.com).
Van Eikema Hommes, De Bruijn, Hermens, Wallert 1999. Still Lifes: Techniques and Style. The examination of paintings from the Rijskmuseum. Rijksmuseum, Amsterdam.

Dutch Fine Paintings Ltd.

Old Masters: painting tricks

Rembrandt van Rijn
Portrait of a Woman, Possibly Maria Trip (1639)
Rijksmuseum, Amsterdam

I often paint dark backgrounds. Learning about old techniques, I aspire to approximate those incredible backgrounds of 17th C Dutch painters, using certain pigment mixes and optical tricks. Lately I have been thinking a bit more about further pushing the suggestion of, in particular, space within that darkness. How did someone like Rembrandt create such rich and dark backgrounds and at the same time suggest such optical depth?

A lot goes on in there: backgrounds, called ‘negative space’, serve an important design purpose within the composition and ca be complex – not just a slab of black paint. They are tricky to do well but things make sense when you look at the current knowledge around old techniques. Every time I get the chance to say hi to the old folks in museums, I look at backgrounds as much as at the other elements in their paintings.

Tricks

As is to be expected, 17th C Dutch painters used several tricks to create their fabulous backgrounds. For example, they used a mix of umber and ultramarine blue which creates a rich dark with a warm or cold appearance depending on the ratio, type of umber, any hints of additional colours as well as the underlying paint. Warm backgrounds were often preferred in order to emphasize those lovely crusty lead white highlights (Rembrandt was particularly good at this). A mixture of umber and ultramarine blue creates a much deeper and richer dark than a black paint can ever achieve.

To enhance the optical illusion of depth a dark pigment was glazed on top once this layer was dry. A glaze is a pigment suspended in a greater quantity of oil (linseed, poppyseed etc) than used for underlying layers of paint, resulting in a transparent paint which can be used to optically mix colours. For example, you can make a yellow look green by painting a blue glaze on top, vs mixing a green paint. This type of optical mixing is a prowerful tool and can be likened to the effect of sunlight seen through a stained glass window. Due to light bouncing about in additional paint layers an optical illusion of depth is created: a rich, deep background. In 17th C Holland the pigment which was commonly used for glazing dark backgrounds was sourced from the peat-rich region around Cologne and Kassel in west Germany.

A rich and deep background which is not black, and the optical effect of sheer fabric on skin through scumbling (see below).
Rembrandt van Rijn, details of Portrait of a Woman, Possibly Maria Trip (1639)

Rijksmuseum, Amsterdam

Scumbling

Additional illusions of texture, space, depth and atmopshere can be generated by the use of scumbling a white on top of underlying darker layers. Scumbling is the ‘dry’-brushing or scrubbing of paint onto the painting surface, a practice that was already in use around the time of Titian (1490-1576). This opaque application of paint can be used to create a range of illusions as it allows the painter to push optical effects: texture where the brushed-on paint highlights undulations in the paint surface, sheer fabric over skin (see Rembrandt’s painting of Maria Trip above) or a cooling effect, making the area bluer, therefore suggesting an atmospheric perspective or haze much like you see in a distant landscape. If you are Turner (1775-1851) you use scumbling to give a distant, misty look to your landscapes and sky:

J. M. W. Turner
Lake of Geneva from Montreux (c. 1810), Los Angeles Country Museum of Art

Scumbling was also used in still life over the centuries; Chardin (1699-1779) for example was an expert at suggesting space extending beyond the main subjects in a painting. He additionally used scumbling in combination with his colours to suggest a diffusing light across this paintings, with certain areas painted more ‘strongly’ than others. To fully appreciate the optical effects he created his paintings were to be viewed from a distance: the art critic Diderot is known to have said of Chardin’s work: “Move away, and everything creates itself and reappears.”

Jean-Siméon Chardin
Glass of Water and Coffeepot (c. 1761), Carnegie Museum of Art, Pittsburgh
Still Life with Game (c. 1750), National Gallery of Art, Washington

Further reading:
Video (1.15min): Portrait of Maria Trip: https://www.rijksmuseum.nl/en/stories/one-hundred-masterpieces/story/portrait-woman-maria-trip
Portrait of Maria Trip: https://www.rijksmuseum.nl/en/collection/SK-C-597
How to look at a Rembrandt like a conservator: https://www.queensu.ca/alumnireview/articles/2019-08-09/how-to-look-at-a-rembrandt-like-a-conservator
Jean-Siméon Chardin: http://en.wikipedia.org/wiki/Jean-Baptiste-Sim%C3%A9on_Chardin
JMW Turner: https://en.wikipedia.org/wiki/J._M._W._Turner

Dutch Fine Paintings Ltd, 2022.