|
|
Ancient Egyptian Art:
|
Throughout our lessons in the Chemistry & Art class, we have come to learn about the close relationship that Art and Chemistry do, in fact, share with each other. Although it doesn’t seem as apparent to the non-scientific thinker, Art cannot be executed or produced without the help of chemistry. For instance, in very basic artistic terms, the pigments used to produce paint, rely heavily on the use of chemical binding, in order to make the pigment adhere to various surfaces. We were specifically interested in this particular relationship when drawing up proposals for our final class project.
After doing some extensive reading, we finally drew our inspiration from our life-long fascination with Ancient Egyptian Art. The Art, and the techniques used to produce them, has fascinated generations and has inspired them to imitate them to the best of their abilities in order to produce some of their own culturally distinctive art. We investigated some of the chemical elements of Ancient Egyptian Art, and asked ourselves key questions: What cultural and religious importance do pigments bear on Ancient Egyptian Art and how were the pigments produced? Creating the various pigments is one thing, but the determining chemical factor is the application process of these pigments unto the varying surfaces the Ancient Egyptians sought to decorate. How were these pigments applied?
In order to make their pigments adhere to the varying differently natured surfaces, Ancient Egyptians developed a technique of chemically binding pigments with a “binder” to produce a paste which resembles the material which we have come to understand as paint. The dry, inorganic and insoluble nature of pigments requires a binder, usually an organic material, in order to adhere to a surface. The Ancient Egyptians experimented with a lot of binders, such as gum arabic and egg tempera, and sought to find the most appropriate binder for a particular surface. The Ancient Egyptians would then use this prepared paint to lavishly decorate objects, papyrus and tomb walls, which were intended to capture the beauty of the Pharaoh culture, as well as last into the after-life and "eternity."
In our final project, we seek to retrace the steps taken by Ancient Egyptians to prepare pigments and binders in order to create paints that are most appropriate for the various surfaces and produce the boldest and most lasting effects. We will bind the pigments with three different binders: a commercial gum arabic, a honey gum arabic following our own recipe, and finally an egg tempera produced from egg yolk. We will then test these paints on three different surfaces and observe their different effects. First, we will apply the paints to a regular, commercially produced paper, such as computer paper also to get a feel for the paints we will be using in our experiment. Then we will test the paints on slabs of limestone that we had collected from the Sewanee Domain that are physically similar to the stone surfaces used in Ancient Egyptian tomb or pyramid walls. We will also test the paints on papyrus, purchased via the internet, and attempt to imitate the qualities of Ancient Egyptian scrolls. We will ultimately have to decide which kind of binder would serve best on what kind of surface. We wish to discover, which pigment/binder/surface combination will lead to the best quality results. We want to uncover the secret as to why Ancient Egyptian Art, which had been created using "simple" means, have been sophisticated enough to endure through the many centuries.
Hypothesis: Due to its texture, the egg tempera binder will provide us with the most optimal paint for the cold limestone surfaces, whereas the gum Arabic binders will be most suitable for the papyrus and paper surfaces. We predict that the paints composed of either of the gum Arabic binders will fail to adhere to the cold surface of the limestone slabs.
Controls: pigments, experimental procedures, tools and materials.
Experimental Variables: three different binders, including egg tempera, honey gum Arabic and commercial gum Arabic, which will each be tested on three different types of surfaces, inlcuding limestone, papyrus and computer paper.
"In Ancient Egypt, color was an integral part to the substance and being of everything in life" (Ancient Egypt: the Mythology). The color in the art work would depict what the nature of the work signified. "For instance, when Amon was portrayed with blue skin, it alluded to his cosmic aspect. Osiris’ green skin was a reference to his power over vegetation and to his own resurrection" (Ancient Egypt: the Mythology). Not all the colors were symbolic; many times the different colors would be to separate large group images from each other. The Egyptians used six colors that were obtained from mineral compounds, helping them to retain their bold color over time.
The color green (wadj) represented new life and vegetation. This idea of re-birth is important when using the color green in art works. The significance of green representing the afterlife can be seen in the Book of the Dead (Chapter 77), were it says the dead will turn into a falcon "whose wings are of green stone" (Ancient Egypt: the Mythology). The pigments for making green paint were obtained from ground malachite, which symbolizes joy and growth. Green could also be obtained from mixing oxides of copper and iron with silica and calcium. The significance of the colors, and their important meanings was highly acute in that it helped the deceased reach their destination of the underworld.
The color red (desher) represented life and victory as well as anger and fire. The Ancient Egyptians, during celebrations, would paint their bodies with red ochre signifying their life. The color of red could take on the meaning of evil or victory depending on the situation represented in the paintings. Red was used for the skin tone of the Egyptian men in artwork, but this carried no significant connotations. The red pigment could be obtained by Egyptian artisans by using red ochre, an oxidized iron compound .
The color white (hedj and shesep) represented purity and omnipotence. Since it is a thin hardly visible paint it also represented sacred things. For example, "white sandals were worn at the holy ceremonies" (Ancient Egypt: the Mythology). The pure white color used by the Egyptians was made from chalk and gypsum.
The black color (kem) was a symbol of death and night. Osiris, the king of the under world was known as "the black one." The god of embalming, Anubis, was represented as a black jackal or dog, even though real dogs and jackals are brown in color. Since its connotations with death, black was also associated with the underworld, thus signifying resurrection. The fertile ground consisted of black soil, which lead to the growth and vegetation. The black pigments could be obtained from soot, ground charcoal or burnt animal bones.
The color yellow (kenit, khenet) represented both the sun and gold, signifying eternal and indestructible. "The skin and bones of the gods were believed to be made of gold" showing their eternal and indestructible nature (Ancient Egypt: the Mythology). The divine beings (such as gods and kings) were portrayed with gold skin color. The Egyptians often obtained the pigment by using ochres and oxides.
The color blue (irtui, sbedj) was used in representing water and sky. The symbolism consisted of life and re-birth, due to the expanse of the heavens in the sky and the primeval floods. Blue was also associated with the Nile and the crops the were produced from the fertility of the Nile. "Amon was often shown with a blue face to symbolize his role in the creation of the world, and by extension the pharaohs were sometimes shown with blue faces as well when they became identified with Amon" (Ancient Egypt: the Mythology). The blue pigment Egyptian Blue, could be obtained by combining iron and copper oxides with silica and calcium.
*The information on the significance of the colors in Ancient Egyptian art was obtained from: Ancient Egypt: the Mythology: http://www.egyptianmyths.net/colors.htm
In order to successfully conduct our experiment, we had to take certain steps in preparation to get all of our items that we required together, properly prepared, and ready for testing. Before we began to make any sort of observations, we collected the necessary items we needed.
Items: commercial pigments, commercial binder, honey, eggs, sodium benzoate, chalk, mortar, pestle, glass plate, muller, spatula, computer paper, papyrus, limestone slabs, paintbrushes, Petri dishes, labels, observation book, digital camera, droppers.
On our first official lab day, we did not meet in the laboratory classroom, but instead walked along the Sewanee’s Perimeter Trail and searched for some appropriate limestone slabs that we would use in our experiment. Since we were going to paint the surfaces, we had to look out for limestone slabs that had smooth, flat surfaces. This was rather difficult to do, since we were not going to cut the limestone out of a rock formation, but rather find pieces that had broken away or fallen off naturally. We found several rocks, which we collected in our backpacks and brought back to our dorm room. Since the limestone slabs were naturally rather dirty, we first had to wash them properly. We did this in our dorm room shower, using water only. We used a brush with plastic bristles and gave the rocks a good scrub. We then categorized the clean rocks into separate piles, depending on the binder that was to be tested on it. We chose the smoother and flatter pieces for the egg tempera binder, because we suspected that the egg tempera would reveal itself to be a more appropriate binder for the rock surfaces than either of the gum Arabic binders. The rocks with rougher, bumpier surfaces were to be used for the gum Arabic tests, because we were most likely not going to paint much with them on the limestone slabs, because we predicted they would not adhere to the surface.
On our second lab day, we planned to organize the pigments we were going to use in our experiment. We had decided that there were six essential colors that were symbolically important to Ancient Egyptian art, and therefore decided to narrow our efforts down to these specific colors: black, white, blue, red, green, and yellow. It had originally crossed our mind to use raw materials to make our very own, hand-made pigments, but due to the technical difficulties and limited resources available to us, we settled for commercially prepared pigments that were composed of the same materials that were originally used by the Ancient Egyptians. We collected commercial pigments for only four of the colors, because we decided that we would purchase the Blue Egyptian Pigment from a specialty store in New York and also make our own white pigment out of chalk. Making the our own white out of chalk, would basically give us the idea what processes the other pigments had to undergo as well in order to reach the powdery stage, ready to be used in a binding process. Before taking a further step, we made thorough observations of the physical attributes of the pigments.
 |
 |
 |
 |
 |
 |
Oxide Iron Red |
Crayola Chalk |
Spanish Gold Ochre |
Bone Black |
Chromium Oxide Green |
Egyptian Blue |
In order to make the white pigment out of chalk, we had to obtain a pestle and mortar, so that we could grind up the chalk into a fine powder. We took two pieces of regular school-board chalk, broke them into little pieces and placed them one at a time into the mortar to be properly ground up. We did so by first breaking the chalk piece into even smaller, more manageable pieces with the pestle and then grinding it down using a circular motion as well as applying pressure. When we ground the chalk into a very fine powder, we put the pigment into a separate beaker, labeled it and made observations. We placed the white pigment aside with the other colors, to be used at a later time in our experiment.
 |
Pestle and Mortar used to grind down the Chalk |
Our experimental procedures required us to prepare three different binders, which were to be tested on the three different surfaces. We had designated one to two lab days for each binder. During those specific days, we would only prepare one type of binder, mixed it with only the necessary amount of pigment, and tested the paint on each of the three surfaces. We would use the paints in the classroom and paint the specific examples and designs from the images we had chosen from different books.
The very first binder we tested was the commercial gum Arabic. We did not tamper with any of its components. This binder came straight out of a bottle that we had obtained from the Chemistry department. We recorded its physical attributes in a table.
Before we began to mix the pigments with the first binder, there were several items we needed to obtain: a strong glass plate, disposable Petri dishes, a muller and a spatula. These tools were to be used in mixing the binders with the pigments to produce the paints. When we set up our workstation we could conduct the first test of our experiment.
We began by placing about one tablespoon-sized heap of specific pigment unto the glass-grinding surface. We would then add drops of commercial binder to the pigment heap in 5-drop intervals. This way we could control that we didn't accidentally add too much binder to the pigment, as so make it too mushy, and unnecessarily wasting any extra pigment that would otherwise have to be added. With each five drops of binder that we added, we would use the muller to thoroughly grind the binder into the pigment powder and further grind down any remaining irregularities in the powder. A muller is used in circular motion without adding an extra pressure, since the muller already uses its own weight as pressure. As the binder and the pigments are being mixed thoroughly together, the operator uses the spatula as an additional aid. The flexible tip of the spatula aids in thoroughly mixing the binder into the powder, without losing any of the vital pigments that had been pushed aside during the mulling process. One has to repeatedly use the spatula to collect the paint from the edges of the glass plate or the bottom surface of the muller. Once the pigment and binders have successfully been mixed together into a paste, we collected the paint and placed in individual Petri dishes and observed the varying results. We recorded the results in tables, because each pigment was visibly different and possessed different qualities.
 |
After we had made our first paint using the commercial gum Arabic, we were ready to test it on the different surfaces. We were originally very skeptical of the adhesive nature of the gum Arabic paints, since they resembled watercolors so much and would logically just run off of cold surfaces. We therefore decided to test the first binder on the limestone slabs. We recorded the rather surprising results. In order to use the seemingly dry and useless paints, we had to re-wet them first, using water and a paintbrush. We then also tested the paints on the other two surfaces, computer paper and papyrus. We recorded any observations we made of the binder’s effect on the pigments and on the different surfaces.
 |
Yellow: two tablespoons of Spanish Gold Ochre combined with 40 drops of commercial gum Arabic. White: approx. teo tablespoons of Crayola Chalk combined with 20 drops. Black: two tablespoons of Bone Black combined with 50 drops. Blue: approx. half a teaspoon of Egyptian Blue combined with 5 drops. Green: approx. three tablespoons of Chromium Oxide combined with 65 drops. Red: approx. one and a half tablespoons of Iron Oxide combined with 40 drops.
|
After successfully completing our first test with the first binder, we could test our second gum Arabic binder. This binder was slightly different from the commercial binder because in its making we followed our own recipe. We mixed some of the commercial binder into a beaker and added drops of regular honey and sodium benzoate to it. This was intended to produce a thicker, stickier binder than the commercial binder that we tested previously. Once we produced our own gum Arabic, we followed the same procedural steps of mixing the binders and pigments as those mentioned in the paragraphs above.
 |
Blue: approx. half a teaspoon of Egyptian Blue combined with 10 drops of honey gum Arabic. Green: one and a half tablespoons of Chromium Oxide combined with 50 drops. White: one tablespoon of Crayola Chalk combined with 25 drops. Red: approx. one and a half tablespoons of Iron Oxide combined with 45 drops. Black: approx. one tablespoon of Bone Black combined with 40 drops. Yellow: approx. one and a half tablespoons of Spanish Gold Ochre combined with 20 drops. |
After producing the second paint, we proceeded to test it on the different surfaces and made thorough observations of the wet paint and its reaction to and interaction with the different surfaces.
The final binder we produced was the egg tempera. In order to prepare egg tempera, an egg had to be cracked and the egg yolk carefully separated from the egg white. The egg can be successfully separated by “juggling” the egg yolk carefully between the egg- halves and allowing the egg white to pour over the sides. Once the yolk is separated, the yolk sac is punctured with a needle, so that the inside of the egg yolk, the pure yellow part, can poor out unto the already prepared heap of pigment. The process is difficult and requires attention and a delicate hand, so that the sac does not break prematurely. Also, there is no true way of controlling how much egg yolk is added to the pigment, since the egg yolk varies from egg to egg and cannot be easily controlled due to its slippery nature. The same procedural steps are repeated as described in the previous paragraphs, but this time, the steps have to be taken much faster because the egg yolk will quickly dry up. In order to preserve the egg tempera’s freshness, we sealed the samples into zip-lock bags until the paint tests could be conducted.
Yellow: approx. one tablespoon of Spanish Gold Ochre combined with one full egg yolk. Green: one tablespoon of Chromium Oxide combined with three-fourths of an egg yolk. Blue: half a tablespoon of Egyptian Blue combined with one-eigth of an egg yolk. White: one tablespoon of Crayola Chalk combined with half an egg yolk. Black: one tablespoon of Bone Black combined with three-fourths of an egg yolk. Red: approx. one tablespoon of Iron Oxide combined with half an egg yolk.
|
Once all the binders and pigments were mixed and the paint tests had been conducted, we were ready to make dry observations and draw conclusions from our final results.
| COLORS | Observations While Painting on the Limestone Surface |
| Black | Egg Yolk Tempera: goes on smoothly, covers the rock color, applies effectively, even on the lumpy surfaces, does not dry as fast as the water colors. Gum Arabic: The black works very well, smooth application, thins out a little but it doesn't run on the rock but instead successfully adheres to the surface. Honey Gum Arabic: The black works well with outlining larger images but bleeds into the other paints while still wet, easy to apply to the limestone surface. |
| Blue | Egg Yolk Tempera: very thin paint, dries quickly, grainy and transparent (can see the limestone color underneath the paint). Gum Arabic: had problems with the blue from the start, applies in specks, too runny, shows up a bit but still too weak. Honey Gum Arabic: have to apply lots of water and pigments, improvement in blue application, very wet because the brushes had to be very wet. |
| Red | Egg Yolk Tempera: the red adheres very well to the limestone, thick and covers the limestone's color evenly. Gum Arabic: works very well, not clumpy, very thick, smooth, bright, doesn't need much water (like the black), very distinct. Honey Gum Arabic: kind of brittle solid pigment, colors very bright, luminous, almost glows on the rock's surface, surface is grainy so it's difficult to apply detailed images, pigment should be wetter to evenly distribute the paint. |
| Yellow | Egg Yolk Tempera: somewhat thin paint, but when applied in layers, covers the limestone surface color well. Gum Arabic: weak on the rock, not fully visible, difficult but feasible to draw small images. Honey Gum Arabic: a bit runny, but stays on, the smoother rock surface area makes it easier to paint on, needs thick layers to produce a solid color, somewhat transparent because the rock surface color is seen through the paint. |
| Green | Egg Yolk Tempera: the green is thick, and easily adheres to the limestone surface. Gum Arabic: the green gets runny, in order to use green we have to use a lot of water, so small areas and detailed images are difficult to paint, image becomes unrecognizable, kind of clumpy pigment mixture. Honey Gum Arabic: use a lot of water to obtain the green pigment, very runny, thinner, but improvement with the honey arabic is noticeable. |
| White | Egg Yolk Tempera: really grainy, was not ground up enough with the binder (very poor white color, more of a yellowish white because it was slightly discolored by the yellow of the egg yolk). Gum Arabic: similar to the green, just too runny, hardly shows up as white, too much water, not able to paint detailed images, must apply in specs. Honey Gum Arabic: thin, needs to be speckled onto the rock to see the color, it applies more easily than the commercial gum arabic white, don't need as much water to obtain the color. |
| Colors | Dry Observations of the Paints on the Limestone |
| Black | Egg Yolk Tempera: thick paint, is smooth on the limestone, not shiny, does not run or show the color of the limestone. Gum Arabic: thin watercolor paint, did not run, sticks to the surface of the limestone, but very thin and the paint collected in grooves of the lumpy surface texture. Honey Gum Arabic: works nicely on the surface of the rock, a little thicker than the commercial gum arabic, less of the limestone color is transparent. |
| Blue | Egg Yolk Tempera: a little grainy, but overall a good paint quality on the limestone, does not need to be speckled on the surface during application to show the color. Gum Arabic: very thin, maybe it's due to the texture of the lumpy rock surface but the paint does not show up in certain areas, grainy blue paint needed to be applied in specs so one can see the solid color, thin and transparent. Honey Gum Arabic: very clearly a thicker paint in this instance, does not appear thin, a little grainy upon closer look, but still applied in the fashion of specs to obtain a thick blue color. |
| Red | Egg Yolk Tempera: a thick shiny paint, cannot see the limestone through it, can see a little grainy texture but that could also be the limestone texture. Gum Arabic: very thick, bold like the tempera, does not need a lot of water to obtain pigment in paint form, very smooth, some signs of bleeding on the limestone surface. Honey Gum Arabic: thicker and bolder than the commercial gum arabic paint, still very smooth, no signs of paint bleeding on the rock's surface. |
| Yellow | Egg Yolk Tempera: a more gold and bold darker yellow than the gum Arabic binders, thicker yet somewhat transparent. Gum Arabic: lighter than the egg tempera yellow, thin and transparent (does not seem affected in its thickness of color distribution on the limestone surface). Honey Gum Arabic: thicker yellow than the commercial gum Arabic water color paint, less transparent (bolder color). |
| Green | Egg Yolk Tempera: thick paint, shiny, bold color. Gum Arabic: very thin, transparent to the limestone color underneath, can see where it bled a little and became runny. Honey Gum Arabic: thicker than gum arabic color, but still transparent, bold in color, no weak and not evidence of runny paint. |
| White | Egg Yolk Tempera: very grainy, and yellow white color, hard to see it's color on the limestone since it was not mixed well enough with the yolk binder. Gum Arabic: had to apply in specs, dried very thick and visible, collects in the grooves of the rock's surface. Honey Gum Arabic: collects in the grooves, very easily seen as opposed to the egg yolk tempera. |
Testing Adhesiveness on the Limestone: All the colors and binders are not peeling off of the limestone, the paints withstood brushing and scratching, revealing no signs of decay. All the binders and pigments are able to adhere to the surface of the limestone without flaking. Upon testing the limestone samples for the paints' adhesiveness, we discovered that they could resist peeling or loss of paint when rubbed with fingers. But when the limestone slabs were rubbed against each other, chipping of some of the paint could be observed.
 |
 |
 |
 |
Egg Yolk Tempera Example #1 |
Egg Yolk Tempera Example # 2 |
Honey Gum Arabic |
Commercial Gum Arabic |
| Colors | Observations of Painting on White Computer Paper |
| Black | Egg Yolk Tempera: very smooth and thick application, when placed on top of another color the paints don't mix or run together. Gum Arabic: great application, thick, does not run, great for outlining details. Honey Gum Arabic: applies smoothly, thick, easier to outline, it doesn't need a lot of water to obtain the paint and it does not bleed with the other colors. |
| Blue | Egg Yolk Tempera: the blue is very grainy, hard to see, clear except for specs of blue pigments. Gum Arabic: thin, needs water to get the color to spread onto the paper, spread and runs easily, apply with use of specs. Honey Gum Arabic: grainy, not solid colors, spec application needed. |
| Red | Egg Yolk Tempera: smooth application, did not bleed, dark and thick, bold color. Gum Arabic: thicker paint, goes on smoothly, bold, does not spread since it does not need a lot of water. Honey Gum Arabic: applies smoothly, thick and bold. |
| Yellow | Egg Yolk Tempera: thin so when placed on another color that one shows up, works smoothly, easy application. Gum Arabic: thick, applies easily, does not spread too much, good for coloring larger areas. Honey Gum Arabic: smooth application, thin paint making it transparent, needs to be layered to make the color bolder. |
| Green | Egg Yolk Tempera: smooth application, thick, works well with white background, see the paint brush strokes in the paint. Gum Arabic: very thin, easier to use on larger areas, need spec application to obtain a good color. Honey Gum Arabic: needs a lot of water to obtain pigment, very thin, spreads on the paper. |
| White | Egg Yolk Tempera: adding extra water mixing it together made the color less grainy and more applicable, seen on the white background since it is an off white color. Gum Arabic: hard to see on the white computer paper, thin. Honey Gum Arabic: does not show up on the computer paper, so adding a little red helped give it an off-white color, thin, easily applied, smooth. |
| Colors | Dry Observations of Paints on White Computer Paper |
| Black | Egg Yolk Tempera: thick smooth paint, overall good paint. Gum Arabic: thick when not too much water is added, somewhat thinner than the honey gum Arabic. Honey Gum Arabic: thick, smooth, does not bleed on paper. |
| Blue | Egg Yolk Tempera: the smooth surface and white background of the paper does not work well with the blue pigment, it shows off easily the grainy texture. Gum Arabic: grainy, thinner than the tempera, need spec application to obtain visible blue color, no smooth brush stroke application. Honey Gum Arabic: thin and grainy, but does not need to be applied in specs. |
| Red | Egg Yolk Tempera: a dark burnt red, not a cadmium red, shiny, very thick and bold, smooth. Gum Arabic: more of a brown color than red, does not even appear to be red, very thin when adding too much water, smooth. Honey Gum Arabic: thicker and less thin than the other gum arabic paint, does not bleed, smooth texture. |
| Yellow | Egg Yolk Tempera: grainy due to lack of mixing the pigment and binder well, transparent yet distinguishable on the white paper. Gum Arabic: grainy texture, somewhat thin and not as bold, can see traced lines under the color. Honey Gum Arabic: grainy texture, gold color, transparent (can see where the pencil lead was transferred from the traced image). |
| Green | Egg Yolk Tempera: thick yet can see the texture of the brush stroke, bold color. Gum Arabic: thinner and collects in areas of the paper, grainy texture. Honey Gum Arabic: collects in areas on the paper, thin and grainy, applied in specs. |
| White | Egg Yolk Tempera: more grainy due to lack of mixing well, shows up on the white paper since it's off-white. Gum Arabic: off-white color, not easily detected without multiple layers. Honey Gum Arabic: thin, needed to add another color to be able to see it on the white paper, smooth. |
Data Testing Adhesiveness on the White Computer Paper: The grainy textures of the colored pigment paints were easily brushed off the dried images (these consist of: yellow, blue and green). It does not take the paint off of the image, rather it just removes the grainy pigment pieces. To test the paints and binders on the smooth commercial computer paper, we rolled the paper to see if it would cause the paint to flake off, but it had no effect other than the grainy pigment to dust off. We also creased the paper a little to see if this would affect the binding and pigments and cause the paints to flake off, but nothing of significance occurred.
 |
 |
 |
Egg Yolk Tempera |
Commercial Gum Arabic |
Honey Gum Arabic |
| Colors | Observations of Painting on Papyrus (Note: the color of the papyrus has no significance to the adhesiveness of the paints. While the pieces of papyrus are different in thickness, the water color based paints caused the papyrus to warp more than on the commercial paper causing them to curl. |
| Black | Egg Yolk Tempera: thick, goes on smooth, sits on papyrus nicely. Gum Arabic: use of less water makes the color more visible, smooth, bold. Honey Gum Arabic: applies nicely, great for any surface. |
| Blue | Egg Yolk Tempera: the blue is very grainy, hard to apply and see, yet with papyrus does not need to be applied in specs. Gum Arabic: shows up very well on the papyrus, the grainy texture works well with the rough surface of the papyrus. Honey Gum Arabic: still grainy, but shows up more as a solid color paint. |
| Red | Egg Yolk Tempera: thick, easily applied, sticks nicely to surface. Gum Arabic: a thick paint, bold, smooth. Honey Gum Arabic: applies nicely, smooth, bold, thick. |
| Yellow | Egg Yolk Tempera: Shows the surface color of the papyrus since it's a thin paint, applies nicely and smoothly. Gum Arabic: difficult to see since it's a light color and transparent, use multiple layers to make it more visible. Honey Gum Arabic: when placed on top of the white paint it shows up very clearly, on the papyrus it's a little difficult to see so adding layers helps make it a bolder color, applies smoothly. |
| Green | Egg Yolk Tempera: goes on smoothly, thick, sits on papyrus very nicely. Gum Arabic: works well on the papyrus surface, more pronounced, less grainy, no need for spec application. Honey Gum Arabic: shows up nicely on the papyrus, not as thin, needs layers to make it a bolder color, still grainy. |
| White | Egg Yolk Tempera: did not show up on the papyrus due to it's failure in mixing. Gum Arabic: very visible when placed on top of the other colors, use layers to make it more visible on the papyrus, thin (easier to see on the dark papyrus as opposed to the light papyrus). Honey Gum Arabic: easier to see on the dark papyrus rather than the light papyrus, needs many layers to be seen on the papyrus, smooth application, thin, light paint. |
| Colors | Dry Observation of the Paint on the Papyrus |
| Black | Egg Yolk Tempera: shiny, thick, bold, the thick texture causes difficulty in its application since it does not seep into the crevices of the textured surface of the papyrus if it is not applied slowly and with pressure. Gum Arabic: applying the paint too hastily creates little pockets where the black paint is not entered into the crevices of the papyrus, bold, smooth, thick. Honey Gum Arabic: similar qualities to that of the other two binders, needs to be applied to the papyrus in order to stop the black paint from creating areas that are not painted, smooth, bold, thick. |
| Blue | Egg Yolk Tempera: grainy and thin, collects in areas, can see the papyrus color through the transparent blue paint. Gum Arabic: significantly better and more visible on the papyrus than the computer paper. Perhaps the textures surface provides a better adhesive than the smooth surface of the computer paper. Still thin and collects in certain areas, transparent, thin. Honey Gum Arabic: texture of the blue is thin and grainy, transparent. |
| Red | Egg Yolk Tempera: shiny, thick, smooth, bold. Gum Arabic: a little grainy, becomes runny when adding too much water, burnt red color as opposed to the brown color seen on the white paper, bold. Honey Gum Arabic: the dark red masks the color of the papyrus when little color is used to obtain the color from the paint, not a brown red as it was on the computer paper, bold. |
| Yellow | Egg Yolk Tempera: grainy and shiny, thick and not very transparent. Gum Arabic: thin unless reduce the amount of water used to obtain the paint color, shows the background of the papyrus color more significantly than the tempera or the honey gum arabic unless applied in layers. Honey Gum Arabic: a less gold and more yellow color, thin due to its lack of layers when applied, bold and slightly grainy. |
| Green | Egg Yolk Tempera: thick and bold on the papyrus, a little grainy, shiny, not too transparent. Gum Arabic: somewhat thin due to its water based binding, it is somewhat transparent but relatively bold on the papyrus, grainy. Honey Gum Arabic: more bold than the commercial gum arabic paint but still slightly transparent, grainy. |
| White | Egg Yolk Tempera: due to the lack of quality in making the paint the white is not apparent on the papyrus. Gum Arabic: after adding a couple layers on top of one another the white paint became very apparent when it dried, thick application yet still slightly transparent, smooth. Honey Gum Arabic: fairly bold color when dried with a couple layers, smooth texture. |
Data Testing Adhesiveness on Papyrus: The grainy texture of the green, blue and yellow all lost a little pigment when rubbed or scratched. No significant effects occurred. To test if the paints would crack and flake off, the papyrus was rolled and creased, and no effect occurred other than more pigment grains coming loose and falling off.
 |
 |
 |
Commercial Gum Arabic on Light Papyrus |
Honey Gum Arabic on Light Papyrus |
Egg Yolk Tempera on Light Papyrus |
 |
 |
Commercial Gum Arabic on Speckled Papyrus |
Honey Gum Arabic on Speckled Papyrus |
Our results reveal to us that the type of binders is not essential to the quality of adhesiveness to the surfaces nor do the surfaces affect the adhesiveness of the paints. The difficulties we faced are based on the pigments themselves. Certain pigments require more or less binder than others to produce an applicable paint. While the surfaces offer us the option of determining which we prefer, there is not a lot of significance in the effect of the binder and adhesiveness of the paints. Rather, the surfaces will either help or hinder whether a paint is visible on that particular surface.
The surface texture of the computer paper was too smooth and silky for the blue and green paints to become visible with or without the grainy look. The surfaces of the papyrus and the limestone were more optimal for the blue and green paints (in each case: the egg tempera and the two gum arabic binders). The surfaces also affect the visible color result and application process for each paint, but regardless, each binder we used was adhesive to each of the surfaces we tested them against, although each with varying visible and textural results. The white paint, for instance, was adherent to all surfaces, but more pronounced on the darker surfaces of the limestone and papyrus in comparison to the already white computer paper. Except in the case of the egg tempera, there was a problem with the visibility of the white paint because of the chemical nature of the chalk in the white paint, which is not compatible with the egg yolk in the egg tempera binder.
The binders, of course, had a profound effect on the visual aspects of the paint. The egg tempera is significantly different in texture as opposed to the two gum arabic binders. Whereas the gum arabic binders are "reactivated" by water and also thinner, the egg tempera is much thicker and slimier because of the physical nature of the egg yolk that it contains. Because of this difference in the thickness of paints, the egg tempera is bolder than the other two water color paints made of the gum arabic binders. And while the two gum arabic based paints are very similar to each other in texture and applicability, slight differences can still be determined. The honey gum arabic produces a slightly thicker paint (due to the thick, sticky honey it contains) and therefore has a bolder color result than the commercial gum arabic. This effect can be prominently noticed on the limestone surfaces, when observing the contrast between the thin, runny, and transparent paints of the commercial gum arabic and honey gum arabic. With the use of different surfaces, we were able to note the slight differences in the gum arabics binders and paints that did exist. The honey and the sodium benzoate in the honey gum arabic binder caused the paint to be thicker than the commercial one, and therefore produce bolder colored paints. We concluded, the thicker the paint, the bolder it appears on the different surfaces.
The more significant factors in the creation of the paints were the pigment themselves. Each pigment appears to have most of the same characteristics when used with each binder, but among certain colors notable differences arose in their appearances, depending on the binder to surface texture combination. Among these paints, the Blue Egyptian paint seemed the most unique.
Blue: The Egyptian Blue pigment was used to create the blue paint for our experiment. When testing its adhesiveness, it had the same characteristics on each of the surfaces regardless of which of the three binders. The application of the blue was different for each surface, since the texture seemed to affect the visual outcomes of the paints. The pigment, however, was the most difficult to make into an applicable paint. The common quality of this pigment with each of the binders was its grainy texture. The blue pigment proved difficult to apply and failed to have a visually pronounced effect on the surfaces. Because of the different surfaces and binders, the blue appeared either prominently and bold or hardly at all. The texture of the blue pigment was grainy and required more work during its application to the varying surfaces. On the limestone surface, for instance, we had to either dab it on in blots, or apply several coats, in order to leave a noticeable trace of the color. The pigment is Calcium Copper Silicate (CaCuS4O10), which makes it insoluble in acids, even in warm temperatures. Because of its chemical properties, it is not advised to use it with tempera, oil or encaustic binders. Its ideal use would be in fresco art. Because of the similar difficulties we observe when using this paint, it becomes apparent that the binder does, in fact, play a significant factor in producing applicable paints from pigments.
Red: The pigment used to produce the red paint (in accordance with what the Egyptians used) was the oxide iron red. The red pigment (besides some visual differences based on the surface areas and binders) yielded the same smooth dark texture for each binder and provided no difficulties with adhesiveness, and when mixing with each binder it was smooth (did not dry quickly and was smooth and did not clump into sections).
Yellow: The pigment used in creating the yellow paint was Spanish Gold Ochre. Ochres requires a high percentage of binder. This is a natural iron hydroxide. The pigment is obtained from mines in the earth and ground up and washed to create the ground yellow ochre pigment. This pigment yielded the same grainy texture, yet was applicable and smooth to mix with the binders. When creating the pigment to paint, the yellow ochre was easy to work with and smoothly mixed with each binder.
Green: The pigment used in the creation of green paint for this experiment was chromium oxide green. Though this pigment was not fist made until 1809, it still closely resembled the pigment used by the Egyptians: Malachite. Its chemical properties consist of Andyrous chromium senquioxide, Cr2O3. "The relating weak ligand field of the chromium-oxide bonding at the chromiums produces color in a similar manner to that of the emerald green," (http://www.jcsparks.com/painted/pigment-chem.html). The green paint for both gum arabic binders, was clumpy and was similar to the making of the blue pigment. The tempera expressed similar problems when creating the green paint. This shows that the pigment is the significant factor in the creation of paints, since it is the overall determinant to weather the paint will be smooth or grainy, or clumpy.
White: In order to obtain white paints, ground up chalk was used. While the binders and surfaces affected its visual representation, the adhesive nature of the paint remained the same. The pigment was able to become a paint with any of the binders, but the binding process was more difficult with the egg tempera (it required a lot more more mixing than the gum arabic binders). Just as the Egyptians used chalk to obtain a white paint, so, too, did we.
Black: Bone black pigment (like the Egyptians who would take burnt animal bones as the pigment in creating black paint) was used to create the black paint. The black pigment proved easiest to create a paint for and mix with all the binders and apply to all the surfaces.
The significant factor in creating paints depends on the pigment, and its compatibility with the binder. It is the pigment that is the significant factor in the quality of the paint (needs to be mixed with the most appropriate binder to yield the best paint). It is apparent the surfaces affect the paints visually, but the three binders were all adhesive to the surfaces. We began this project trying to discern which of the binders and surfaces would produce the best results. The egg tempera did of course produce the most bold colored paint, while the two gum Arabic binders yielded only a very thin paint. In the end, we felt that testing the adhesiveness of the paints would be more likely to be an obstacle for artists, rather than the visual aspects the binders and surfaces would have on the paints (it is fairly obvious that the egg tempera would be thicker than the gum Arabic watercolors). We determined that both the water colors worked best on the papyrus and white commercial paper, as oppossed to the limestone surface (yielded bolder colors) and was more addhesive to the paper, though the papyrus did warp due to the water in the paints. The egg tempera worked well on any surface, but provided the best results (visually) on the limestone. The adhesiveness of the tempera and the watercolor gum Arabic paints relied on them not being rubbed together, since it begins to rub off of the surface of the rock. Depending on the desired visual effects each can yield, all binders and surfaces are adhesive. The pigments did provide instances (blue and green) which did not produce a solid, bold paint.
1. Ancient Egypt: The Mythology: http://www.egyptianmyths.net/colors.htm
2. A History of Pigment Use in Western Art Part 1: http://www.pcimag.com/CDA/ArticleInformation/coverstory/BNPCoverStoryItem/0,1848,115623,00.html
3. Earth Pigments: http://www.danielsmith.com/learn/inksmith/200208/
4. Chem & Art Website: http://www.sewanee.edu/chem/Chem&Art/Detail_Pages/Pigments
5. Mysteries of Egypt: Scribes: http://www.civilization.ca/civil/egypt/egcw05e.html
6. Pigments and Their Chemical and Artistic Properties: http://www.jcsparks.com/painted/pigment-chem.html
Images and color references came from these sources:
Dr. Bordley and the Sewanee Chemistry Department, Kremer Pigmente Co., Dick Blick's Paper Company