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Bison Bone Black

J. Klima, Bone yard, Michigan Carbon Works, Detroit, Michigan, n.d.

For reasons still unclear to me, I have never been that far from cow skulls. There has always been one in the drawing studio, usually right next to a few plaster sculptures of heads, packed away in a closet of still life objects. The cow skulls are in good condition, bleached white and with but a few cracks. When I was an art student, I drew them regularly and liked the way that there seemed to be an endless supply of craggy, irregular lines running through their form. Now that I teach studio art, I am the one who pulls these bones out from storage for others to draw. My fascination has sometimes been shared. Other times, I have seen a kind of small horror in the eyes of my students that seem to be saying less, “Is that a real skull?!” and more, “Am I going to be expected to draw that?!” I have seen many fake human skeletons in art studios, and a few real ones, but never any fake cow skulls. There seems to be no shortage. Drawing a cow skull is at once easier and harder than it looks. It is hard to completely mess up a cow skull and easy to find something new. I have not once been able to account for how these schools acquire the skulls, and I say that as someone who should know better. I have a cousin who works on a dairy farm.


Cow bones are really the beginning of bones in the studio. Even more interesting, and perhaps more useful, is a shade of paint that goes by the name bone black. The paint gets its name from the black pigment made of calcined animal bone. Today, it might actually have once been part of one of my cousin’s herd.


The general chemistry of bone black is that of burnt and charred remains. One part of this pigment is carbon, the same element that makes up graphite, coal, and diamonds. Bone black is only 10% pure carbon, however (Bergslian, 289). The majority of bone black is calcium phosphate. There are also trace amounts of calcium carbonate. Both of these calcium compounds, in pure forms, are white, and yet bone black is considered one of the darkest blacks available for artistic use. The manufacture of bone black is similar to that of charcoal. The bones must be put in an oxygen-poor environment and roasted in a fire or kiln. This turns the bones into bone charcoal which must then be ground into a very fine powder in order to be used in paint. When the bones come out of the kiln, they retain their original form, but are black and have a spectral luster of all the colors one might find in an oil slick on asphalt. The bones, before they quickly collapse into dust, look as if they have undergone an alchemical transformation.


Painters have been using bone black for thousands of years, likely as long as we have had the ability to make charcoal. European Tenebrists from Caravaggio on employed this black often in their works that had great need of a deep black shadow. El Greco and Goya, infrequent users of actual blue pigments, often used mixtures of bone black with white to produce blue-gray shades (Old Masters Palette). The palette El Greco and Goya preferred, a limited palette of earth colors, black, and white, is often called the dead palette. In this case, the black used really is something dead.

El Greco, Laocoön, 1610-4

Bone black can also be found in India ink, as well as mascara, as it is perhaps surprisingly nontoxic (Product History). The sugar industry uses bone black to refine raw cane sugar into the refined white sugar. That means the sugar in your coffee and bread very likely was processed with bone. For this reason, some vegans abstain from refined sugar and use substitute sweeteners. There is one hypothetical way bone black could potentially be harmful, however. The skulls and spines of animals that are prone to prion-borne conditions like Creutzfeldt–Jakob and mad cow disease are such bones, and they are not used in bone black paint today (Dirty Jobs).


The superlative version of bone black is a deep, velvety black that is just slightly blue. The best bone of all to use was the ivory tusk of an elephant, and it is called ivory black. Rembrandt, another painter with a lineage back to Caravaggio, used ivory black often (Bomford, 44). Today, of course, elephant hunting is prohibitively expensive, though not impossible, and the sale of ivory is increasingly illegal, largely due to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (What is CITES?). Demand for ivory is high enough that many environmentalists do worry that it could drive elephants to extinction. This demand, however, is focused on intact raw ivory and not processed ivory like black paint. Contemporary paint manufacturers confusingly use the terms bone black and ivory black interchangeably, though it is almost always bone black that is really for sale. At the time of writing this paper, I know of only one art supplier, Kremer Pigments Incorporated, that still sells genuine ivory black (Kelley). They obtained the ivory as a waste product from jewelers who possessed the ivory in accordance with CITES, and only have a small, finite supply that may not be renewed.

Rembrandt van Rijn, Self-Portrait, 1660

The current destruction of elephants reminds me of another animal, and this time it is not the cow. I am thinking of the bison of the American Plains. It, too, was hunted nearly to extinction. Only recently have most Americans become aware that the bison did not in fact go extinct, and we have done so through the realization that one can now purchase a thing called a bison burger. The story of the bison is long and complicated. Its depopulation in the 19th century helped spur the conservation movement. For the Native Americans of the Plains, who hunted and survived on bison, the species was sacred and divine. Finally, oddly enough, the bison was responsible for a short-lived boom in bone black production. Bison bone black was the color of black at the end of the 19th century. Wrought iron gates, steam-engine trains, and even black leather Victorian boots would have been potentially painted in this shade of black.


The story of bison bone black might really have begun in 1869. This was the year when the Union Pacific and Central Pacific lines connected, forming the first transcontinental railroad in North America, formally connecting the Plains to the industrial world. I want you to picture those first trains, driven by steam engines and shovelfuls of coal crossing over the grassland. Those trains might have been painted black, but it is not likely that it was bone black. More likely it was lamp black, which is really a fancy name for soot. These trains were industrial machines painted in industrial waste, to not put too fine a point on it.


The United States wrapped up more than just the Civil War in the 1860s. There were also wars with the Native Americans. The Treaties of Medicine Lodge and Fort Laramie of 1867 and 1868 divided the Plains into federal territories for future Euroamerican settlement and tribal territories that were designed specifically to accommodate nomadic hunting of bison (Isenberg, 115). One of the U.S. delegates who worked on these treaties was no less that General William Tecumseh Sherman, the same military leader who is now famous for instituting a “scorched earth” policy in the Civil War, perhaps one of the earliest modern instances of total war.

The treaties did give various exceptions for Euroamericans to enter tribal territories, and it was clear to Sherman and his fellow delegates that they expected an eventual depopulation of bison to render the whole agreement moot, something they did not share with the Native Americans. The long-term agenda was to relocate the tribes onto reservations, but these Plains tribes were nomadic societies that were averse to being sedentary or agricultural. Only the destruction of the bison could allow this “pacification” to succeed.


While Native Americans had traded bison “robes” with Euroamericans for some time, the demand for hides dramatically increased in the 1870s, as the American tanneries in the Northeast experienced a shortage that doubled the price of leather (Isenberg, 117-8). Now connected by rail back to the Northeast, it was easy to ship bison hides to the tanneries. The meat of the bison was not nearly as saleable as the hides and most carcasses were left to rot. This was a very different form of hunting compared to the likes of the Lakota, who made use of all parts of the bison and wasted nothing. Like the miners of the 19th century gold rush, few of these adventurous hunters ever made a fortune and most would ultimately be happy to just break even (Isenberg, 132-3). American mythology has saved one of these men for posterity: William Frederick “Buffalo Bill” Cody (Buffalo Bill). He was known for being able to nab quite a few bison in a single stand, but his fortune and legend was really cemented by his traveling Wild West show that toured the world.


By 1883, the big hunt was over, and bison were on the brink of extinction (Isenberg, 134). The Native Americans of the Plains were relocated to reservations. Starting in the 1870s, as the carcasses began to pile up, bones began to be more important than leather. In cities like Detroit, Philadelphia, and St. Louis, carbon works industries were being established (Product History). Carbon works, while sounding like they might have dealt primarily with coal, would be better seen as predecessors of the petrochemical industry. The bones were calcined into bone charcoal and then bone black. The initial industrial demand came from sugar companies for refining (Ibid). By 1880, bone black was also being used as a fertilizer, and carbon works quickly diversified into even more bone-based products (Ibid). It was at this time that bison bone black became an industrial pigment. Also, it should be noted that carbon works were by no means a small business. In 1892, Detroit’s Michigan Carbon Works was considered the single biggest industry in the not-yet-motor city (Ibid).


The gathering of bones is perhaps the darkest and most ironic chapter of all. Farming was difficult in the Plains during this time, on account of moderate drought for several years (Isenberg, 134). Homesteaders and Native Americans on reservations both had trouble during this time. The very tribes that had hunted bison for millennia and had been pushed into reservations would now be the ones to carry the bones to the rail yards that would be heading back East. The one part of the skeleton that was often not sent back was the skull, but not so much because of any symbolic value or risk of prions but because the hollow skull took up too much space in the rail cars (Heffernan). In photographs from this time, it is not uncommon to see charnel walls of these skulls. In Topeka, Kansas there was even a street paved with bison skulls (Ibid). When the bones did come back to the Plains, they came back as a black dust to be tilled into the soil and as the shade of a distant black train on the horizon that incessantly exhaled gray smoke. These trains might not have been painted lamp black. Rather, these trains might have been painted in the bones of the once sacred animal that roamed the Plains.


By 1896, the Plains had been cleared of bison bone (Product History). Most carbon works had anticipated the upcoming scarcity and stockpiled when possible. Ultimately, they adopted phosphate rock as a replacement to bone black in fertilizer and bones from livestock would replace the bison for bone black. In the early 20th century, the petrochemical industry more or less eclipsed the carbon works industry and it synthesized carbon black, a newer, cheaper black pigment that came from crude oil (Ibid). Today, there is only one American company left that produces bone black. It is the Ebonex Corporation of Detroit, a company that is all that remains of Michigan Carbon Works after a series of mergers and splits (Ibid). It currently has 2 full-time employees (Dirty Jobs). By comparison, the current population of bison at the start of the 21st century is estimated to be a half million (Engel). This is a great growth from the low of a mere thousand bison at the end of the 19th century, though nowhere near the tens of millions the population was estimated to once be before the modern era.


When we look at a painting and see black, maybe we see a shadow. Maybe we see the black paint as a symbol for death. What might be less obvious is that, at least in this story of bison bone black, there is death on many different symbolic and temporal levels. And strangely, there is life, as well. The pigment, when used in a painting, can stimulate the eye indefinitely. The actual bison are on a rebound, and bone black, as a pigment for art, has returned to the small niche of demand that it has held for millennia.




Bergslien, Elisa. An Introduction to Forensic Geoscience. West Sussex: Blackwell Publishing. 2012. Print.

Bomford, David. Rembrandt. London: National Gallery Company Limited. 2006. Print.

“Buffalo Bill.” New Perspectives on the West. PBS. Web. 28 March 2014.

Dirty Jobs. “Bone Black.” Discovery. 9 February 2010. Television.

Engel, Matthew. “The Buffalo Roam Again.” The Guardian. Web. 7 February 2003.

Greco, El. Laocoön. 1610-1604. National Gallery of Art, Washington, D. C. NGA. Web. 29 March 2014.

Heffernan, Tim. “Where the Buffalo Roamed, a Strange and Morbid Economy.” Bloomberg View. 30 August 2012. Web. 28 March 2014.

Isenberg, Andrew C. “The Wild and the Tamed: Indians, Euroamericans, and the Destruction of the Bison.” Animals in Human Histories: The Mirror of Nature and Culture. Henninger-Voss, Mary J, ed. Rochester: University of Rochester Press. 2002. Print.

Kelley, Brian. “Questions about Ivory Black, Genuine.” Message to Eva Eis. 25 April 2014. E-mail.

Klima, J. Bone yard, Michigan Carbon Works, Detroit, Michigan. n.d. Detroit Public Library, Burton Historical Collection, Detroit.

“Old Masters Palette: The Palette of Goya.” Natural Pigments. Web. 28 March 2014.

“Product History.” Ebonex Corporation. Web. 28 March 2014.

“What is CITES?” Convention on International Trade in Endangered Species of Wild Fauna and Flora. Web. 5 May 2014.

Van Rijn, Rembrandt. Self-Portrait. 1660. Metropolitan Museum of Art, New York. Met Museum. Web. 29 March 2014.