Bone Black

Bone Black Tempera on Bristol

 Although there were various methods of making a charcoal black (grape vines, walnut husks, etc.), I have been fascinated with making bone black lately.  This type of pigment can be made from any type of bone, though the bones of fish or birds are the easiest to use because of their size and increased surface area.  

Charcoalized chicken bones after removal from coals

For this experiment, I took the bones of a roast chicken and, after the meat was consumed, made a bone broth from the remnants.  This makes a healthful soup and also makes the bones soft and easy to clean.  Making bone black requires that the bones be entirely sealed off from air in order for them to charcoalize.  To accomplish this, I sealed them in several layers of aluminum foil before placing them in the coals of a fire.  I just left them there as we cooked dinner over the flames, and after we ate, I removed the foil packet and allowed it to cool.  The blackened bones within can then be powdered and worked up in the same method as any other pigment.

I decided to test mine out in an egg tempura that would seal the pigment in as it dried, avoiding any smudging later on.  It ground up so smooth and the warm black gave a rich, intense color.  I definitely look forward to making more of this in the future!

Elderberry Experiments: 2024

Sap green paint from unripe blue elderberries

In Theopholis' "Divers Arts" he mentions a green pigment from elderberry. The Sambucus nigra species is most common in Europe through the Middle East.  The most common in the United States is a sub-species of this, Sambucus canadensis, that does not grow as large, has a pale yeast that grows over the berries causing them to appear blue, with lower levels of total anthocyanins (provide pigment). 

Ripe and unripe blue elderberries along with a small piece of ochre.

In experiments this past summer I used what was available to me: blue elderberry.  Although the anthocyanin levels were lower, I hoped to get at least a paler version of the green that Theopholis might have used.  Since anthocyanin levels are at their highest when the berry is ripe, I suspected the ripe berries might be shifted with the addition of an acid to a green color like the purple of the iris.  However when I tested this, shifting through the pH range by addition of ammonia, and vinegar or lemon juice, I got shades of pink to a grey blue.  I decided to try the unripe berries.  These little orbs were mostly filled with hard, colorless seeds.  But the small amount of flesh and skin burst with intense, sap green!  

Columns of testing, from left: fresh green berry, fresh ripe berry, air dried berry

I tested with a variety of additives, and the most vibrant green seemed to be from adding a small amount of alum water.  Even after taping a sample in the window for several days, the color maintained surprisingly well!  Perhaps artists of Theopholis' time were using unripe elderberries to make their green paint?  To test further, I would like to repeat this experiment with Sambucus nigra next year to see if there is any difference.  

Freshly ground green elderberry paint

Mulling Stones: Earth Paints

The oldest art form we know of are cave paintings, some dated at more than 50,000 years old.  And the paint used in these paintings is usually ochre!  Ochres are earth pigments, highly silicate colored earth, found worldwide in clay beds.  It’s often perceived as “soft rock” or the pigment of the clay itself, it’s a mixture of ferric oxide (iron) and varying portions of clay and sand.  They will usually naturally be found in browns, yellows and oranges.

Pointing out ochre stones that the gophers have kindly brought to the surface.  It easily crumbles.

Ochres are very stable pigments that do not fade or dull in the presence of UV rays (like anthocyanin) or air (like chlorophyll).  The only instance where they may shift color is in the presence of intense heat.  In the middle ages in Europe, pigment makers would heat the natural gold ochre of the landscape, thus causing the ochre to change from gold to red. The process of turning yellow ochre red can be seen in areas that have just been afflicted with wildfire.  Natural ochres have been heated enough by the fire to turn red where they originate, probably because of copper inclusions that redden with heat.  This is also where we get modern paint terms like “Raw Sienna and Burnt Sienna” or “Raw Umber and Burnt Umber”. The raw refers to the ochre as it comes from the land, while the burnt refers to the color after heat is applied.  Those terms also not where the raw material originated.  “Umber” and “Sienna” are both locations in Italy.  So you can name your color by wherever you harvest it from (ie “Raw Cottage Grove”).  

The ochre stones at top have all been located on our property.  The lids contain the same golden ochre at different lengths of heat application.

There is a similar pigment whose slightly differed chemical composition alters its color greatly.  Often called “Green Earth” gets its color from iron silicates (glauconite and celadonite) rather than iron oxides.  Similar in its green color is copper carbonate, although this stone ends up being quite a bit hard, therefore taking more effort to prepare as a pigment.  Calcium carbonate (chalk), gypsum, and limestone are all soft whites that have been used as opaque whites.  

This sample of copper carbonate is more vivid in person and was found In the Oregon Cascades.

Then theres the famous ultramarine from lapis lazuli.  This was a precious color in the middle ages because it was both difficult to obtain as well as difficult to prepare.  In the middle ages, lapis was only mined in what is presently Afghanistan, so most of Europe had to have it shipped in.  Only the highest quality would make a vibrant blue.  To prepare this ultramarine blue, the very hard stone had to be mulled, but not over-mulled.  Once the particles passed a certain size, the refraction changed, causing the pigment to appear more and more ashy the smaller it got.  In some manuscripts, you can see the texture of the paint as it could not be mulled finer without loosing vibrancy.  And in the European middle ages, vibrancy was equal to beauty.   Malachite performs in a similar way to give a bright green.

While just about any stone can be used to make a paint pigment, there are many that were used, created bright, vibrant colors, but many modern scribes refuse to use due to potentially negative health effects if not handled properly.  Vermillion is the name of the pigment made from naturally occurring cinnabar (Includes sulphur and mercury) or from heating sulphur with mercury.  Vermillion gives a red color that was used in both medieval Europe, Asia,  as well as pre-Columbian Americas. Realgar is more of an orange red, but is very arsenic laden.

Orpiment gave a clear, sparkly yellow and could be found near volcanos, but its main component is lead.  Azurite was often used as a budget ultramarine.  It couldn’t attain quite as vibrant a blue, but it was close and much more ubiquitous.  However, when it was ground into a powder to use as pigment, it off-gassed mercury cyanide.   And then lead white has it’s warning in it’s name.  To create lead white, lead strips were fumigated over vinegar or urine.  

The process of mulling stone pigments is largely the same, just the duration will differ.  Aside from your pigment material, you’ll need a hammer and cloth, mulling board and muller, as well as safety equipment of dust mask and safety glasses.  Concerns include bits of flying rock as well as inhaling the dusts that can cause silicosis.  Mulling boards and mullers can be found by glassworkers, but a smooth, tempered glass cutting board and flat-topped (no embossed numbers) glass electric insulator can work just fine.  

You will also need to add some type of binder during the mulling process.  What you add will determine your end product.  If your goal is simply to grind the pigment powder or make a very basic paint, water will suffice.  Eggs are also a common binder.  In the pre-colonization Pacific Northwest, fish eggs were added with the albumin stabilizing the paint.  In Europe, chicken and quail eggs were used in a couple different ways to create paint.  Eggs were used in glaire and tempura as well.  More binders include hide glue, gum arabic, and seasoned linseed oil.  For more information on the different binders and the paints they create, check out my article here: http://www.growwildmychild.com/2024/06/historic-paints-on-metal.html

For the sake of brevity, this article will discuss the use of water as binder, to create a pigment powder that can be reconstituted with any binder again at any future date.  To begin, chip off the amount of pigment you’d like to use, usually no more than a couple tablespoons worth.  If the original material is hard, I like to wrap it in a stout cloth, don protective equipment, and chip pieces with a hammer over a harder rock.  If available, sometimes it’s helpful to further reduce the particle size by grinding in an iron or hard stone mortar and pestle.  Once your materials particle size has reduced to sand or smaller, place it in a mound in the center of the mulling board.  Indent the top and prepare about half as much binder as you have pigment.  This amount will vary, but it’s easier to add more than have too much.  If you’re concerned, reserve a small amount of ground pigment off the board. 

Mulling the pigment can take anywhere from ten minutes to an hour, depending on the hardness of the stone.  The finer the pigment powder, the smoother and more uniform it will act as a paint.  Traditionally, this mulled pigment was put into small pans or shells for storage.  To reconstitute plain dry pigment, return it to the mulling board and re-mull with your binder of choice.  Once it’s fully blended, it’s ready to be used as paint!  Be aware that some binders (such as gum arabic and egg glaire) can be allowed to dry and reconstitute indefinitely, while others (such as tempera and egg yolk) must be used when they are made.  

***Word of warning: there are paint pigment sellers that claim "earth pigments" who only use a natural ocher base and add modern chemical compounds to give them vibrant colors.  From what I've seen they usually list their processes somewhere on their website.  These are still really fun to play and paint with!  Just know what you have.  

Resources

1. King, H. (2024). “Malachite” from geology.com. Last viewed 5-20-24 from https://geology.com/minerals/malachite.shtml
2. Royal Tennis (2003) “Color Stories” Last visited 5-20-24 from https://www.royaltalens.com/en/inspiration/tips-techniques/colour-stories/
3. Albee, S. (2022) “How Many Artists Were Poisoned by their Paints?” Last visited 5-20-24 from https://medium.com/@sarahjalbee/how-many-artists-were-poisoned-by-their-paints-346a93459b7e
4. Douma, M., curator. (2008). Pigments through the Ages. Retrieved 5-20-24 from https://www.webexhibits.org/pigments
5. Cochran, C. (2024).  “The Deepest Black” Retrieved 5-20-24 from https://christophercochran.me/color-history/bone-black/
6. Webster, S. (2012) "Earth Pigments: Hand-Gathering & Using Natural Colors in Art" Schiffer Publishing.