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Tuesday, September 23, 2014

CLAY, MARBLES, and MORE


Paleography 130

This week in our class we were assigned readings about historical writing and given a choice of several options to write with/about. Another assignment is to spend some time preserving records.
  • Write a report; 
  • Make a quill pen and ink;
  • Make some paper; 
  • Make a cuneiform clay tablet 
sample letters from Wikipedia reading

I chose
     "Read the “Cuneiform” article at http://en.wikipedia.org/wiki/Cuneiform. Using modeling clay or salt dough, create a Sumerian clay tablet (does not need to exceed 3" x 5"). Using a stick, create your own cuneiform stylus."

left: cracking marble; center: wet clay marble; 
As a child, my siblings and I sometimes made marbles from slippery mud left as puddles dried after heavy rain. It would crack in slabs and curl in the sun. The back side of the slabs made excellent marbles that we would sneak into the bottom of mother’s oven. Sometimes they would crumble. We never knew which would and which would not. She was very patient, except when they blew up!

Later I learned that clay must be completely dry or it explodes during baking.

As an adult, I decided to satisfy my curiosity about why some clay crumbles and other bakes well. I checked out a stack of books from the public library and read about clay: ancient pottery and people that made it, firing, kilns, types of clay and where it can be located, and colors, etc. I never thought about colors - isn't all clay gray?

View from Google Earth, Sept 2014, of coulee 

Soil in our area was a clay "mixture." There was a ravine/coulee near my home where I remembered seeing layers and characteristics like the books described. I took a couple of buckets, a shovel, a cooperative spouse, and went for a short hike.

In the coulees there were several slide areas. I knew I was looking for the kind of “slick” feeling mud that dries to a brick-like hardness, but when wet is so sticky that it is almost impossible to wash off my hands. We found it, filled the buckets, and hiked back.

The books described a procedure for “washing” the clay to remove debris, dirt, sand, or other impurities. This involve mixing up a very watery slurry, straining it repeatedly, and letting the clay settle to the bottom (often over a period of days, with repeated stirring and straining). The dirt and most vegetation would float higher than the clay and could be poured or dipped off. The sand and small pebbles came out in the screens and sieves.

Eventually I had several small gallon containers of grayish white clay that resembled the clay I have seen in pottery shops. It was fun to play with the clay and mold it but I had no idea how to bake it, or what else to do – back to the library (pre-internet time period). The things I read about were interesting, but much more work than I wanted to attempt.

small container of dried out hard clay
One book described a process to “ripen” the clay by storing it in certain humid, temperature controlled conditions. Another detailed how some oriental artists bury it for 10 to 20 years to “cure” it, and yet another described how to harden it in large bonfires kept burning for days. Mine went into sealed buckets and was soon forgotten – but, even in long distance moves, never discarded. It had cost a bit of time and effort, and maybe someday I would use it for something.

Approximately 10 years later, while working as an ASL interpreter in a high school art class, I mentioned the clay to the teacher when the class did the unit on pottery. Mr. Brown was excited and curious. He asked if I would be willing to craft a little pot or figurine and let him experiment with baking it.

white spots on back of pig are impurities in the clay
 I made a tiny pig that fits in my hand. He fired it at about 1500° F and it turned a startling reddish-orange. He said that indicates a high iron content. He told me that even though the clay still had a few impurities that it was great, and provided 'firing' details.

before mixing and wedging

I was working 2 part time jobs, and raising a family, so the clay went back on my 'someday' priority list, and after another move took up residence in our garage. That was about 20 years ago. Last week when I read this assignment, I pulled out a small container of it, added some water to the rock-hard block, and Monday wedged it on a piece of old cotton dishtowel for the 'bat' I don't have (to help control the mess and improve consistency). A piece of heavy canvas would be better but this is what I had on hand.


Initially it was extremely soft and wet with harder drier areas but, as I kneaded, it soon became a pliable block of good clay again. I love clay! 

I couldn't resist trying a marble.

I cut a hand size lump and flattened it slightly, then folded the cloth over it and rolled it out. This helps to keep it from sticking to everything including my hands (although when clay is the correct consistency it almost cleans the hands as it sticks to itself, but I was impatient).


Yes that is my good rolling pin in the picture, but it has seen more clay than pies or cookies - a baker I am not. I cut a chunk and put the scraps back into the container.

clay sandwiched between cloth

I dug through my junk drawer and found a pair of abandoned chopsticks, and then went on the internet to learn about the writing and making a stylus. At the bottom of our Wikipedia cuneiform reading there is a helpful video about the writing. (Writing ancient Iranian cuneiform on YouTube by subject-matter expert Soheil Delshad.) I watched it several times and realized that the scribe was using one stick and it seemed to be just a simple rectangle on the end.

chopsticks left over from take out 
Cool!! I like easy. My chopsticks were almost the same shape.

wide end of chopsticks need to have sharper,
more defined corners and edges - not rounded

There were many suggestions for making a stylus, but I was gratified to see many of them suggested using wooden chopsticks. They just needed to be squared a little bit. I felt blessed! I knew I was keeping those chopsticks for something!

examples of practice writing strokes
When I went to school at age 5, we began to learn writing by making straight lines, angled lines, and last of all finally curved lines. We practiced pages and pages and pages of lines. It seemed like forever before we actually began to make actual letters, never mind words. With this in mind I did not attempt to make actual letters or words on my clay 'tablet.' I attempted to just practice the strokes and shapes I had seen and watched.


First I tried it on a scrap of clay.


I learned a lot about patience.
Clay takes a lot of patience. 
I knew that. 
I had forgotten.

Writing takes a lot of patience. I remember shedding buckets of tears when I learned to write with a pen. I kept finding mistakes in what I had already written. My father showed me how to “fix” many mistakes with some creative thinking. For example a 6 that should have been an 8 can just have the extra parts of the top half drawn in place. Whew! I didn't have to be perfect yet.

I still don’t. My tablet was a fun experiment. First I pressed a curved plastic lid along the edges to constrain the ‘text block’ and make it have a bit more eye-appeal. Then I pressed a metal set of leaves onto the lower left corner like a ‘seal,’ or stamped symbol. (When you work in clay you should always inscribe a mark that identifies your work.)


Next I drew along a straight edge with the stylus to divide the writing areas. In the top row I pressed the stylus into clay at many angles, sometimes lifting it higher and sometimes laying it almost flat. I also rotated the stylus so the wider edge was vertical and horizontal. It wasn't looking much like the triangular marks of cuneiform, so I watched the video again. I also reviewed some pictures from our Wikipedia reading.

Extract from the Cyrus Cylinder(lines 15–21),
giving the genealogy of Cyrus the Great and an
account of his capture of Babylon in 539 BC.

Phoenician alphabet

Sumerian inscription in monumental archaic style,
c. 26th century BC

I noted angles and direction of the imprints more carefully, and also noticed that for some of the broader marks the scribe pressed the stylus into the clay more than once at various different angles. I had better success when I tried again.


Then I tried to make ‘writing’ from different places and times on the second row. With my pocket knife, I shaped a smaller stylus with a longer narrower area to 'draw' or make longer marks.

trying other shapes and strokes with smaller stylus

The clay was a lot drier now and almost ideal to draw on and press marks into. It was somewhat stiff but still soft. On the third row I finally tried to mimic some of the letters/words pictured as cuneiform. Some were more pleasing than others; some were a mess. When I left it overnight to dry, it was the texture of leather and could be handled easily. 


This next morning I couldn't even tell it was drier, except that it was no longer like leather - it was stiff. It rained off and on today and my AC kept coming on – likely to remove humidity.

When making marbles it was important to keep them
similar in size to commercial marbles so that we weren't 
accused of cheating.

I got impatient, put the clay on a rack and turned my oven on low. I left the door ajar and set the rack above the open door. After a while, the top was getting fairly dry so I turned it over. The third time I did that it cracked along one of my dividing 'score' lines - maybe they were too deep.

Slip often becomes very 'creamy' but when the piece is dry
and baked only texture differences will be noticeable. 
It also dries more quickly.

I attempted to put ‘slip’ (a thin slurry of clay and water used to stick leathery unbaked clay to itself) on the back.


I wanted it to have the same texture as surrounding areas so I laid the cloth on it and pressed. DUH!! That was silly – and not patient. It broke in several places. That is when I remembered that a "slab" should have uniform thickness. To roll it to an even thickness you place it in between two matching slats of wood. You can also use a ‘form’ or ‘mold.'


I repaired the breaks using the slip and left it to dry. But I just couldn't seem to leave it alone. I moved it again and all my repairs came apart. Lucky for me I already had pictures. I had made it quite thin hoping it would dry quickly - maybe a bit too thin.


When clay is not baked, but has been shaped, it is called greenware. It is very, VERY fragile. I knew better than to move it around. My slab was in a very tender greenware stage, when just uneven finger pressure can cause damage. It was also not uniform in thickness, so even light pressure on the back caused it to crack. To handle a slab at that stage it would need to be moved lying on a flat surface. I didn't handle it properly.


When clay is baked it is much stronger. If this slab was properly fired it could be handled like any pottery plate of the same thickness. When glaze is added it is adds strength to the clay as well as a finish. This clay appears a deceptive soft- white gray, but when fired will become the common rusty, orange-red of a clay pot.


On some web sites showing cuneiform the tablets look much thicker than mine and show a more rounded sloping edge. This might make them much less fragile. If it is not baked, clay can also be recycled. As soon as water is applied, the clay readily returns to a lump that can be reworked.

soaking to become blended with main lump again

This has been a fun experiment and my tablet is going back into the lump – and likely, until my semester is over, back out to my craft room.

Shake a couple times and this is all just 'dirt' again. 
To reuse as clay I would stir and then let some moisture 
evaporate.

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