A Life of Clay: Born in the Opal Mines Graeme Anderson

Appears in the April 2020 issue of Ceramics Monthly.

I was in my mid-40s when an interest in pottery began, and 26 years later, I closed my pottery business. While I still make pots occasionally for experiments or to have raku and primitive kiln firings with friends, either they keep them, or the pots are given to clubs for gifts or to the Australian Opal Centre to help raise funds for a proposed museum.

I’ve often thought that I was lucky not to have made things with clay in my childhood. Of course, during the war years (WWII), probably no schools would have had pottery classes due to power restrictions, lack of teachers, etc. If I had taken classes and had experience with pottery clays, I would not have continued with the difficulties of trying to make pots with clay from the opal mines in the region where I live. So, my main obsession continues to be exploring what can be done with the local clays.

Local Inspiration

My interest in working with clay began when I was mining for opals and living out on the opal fields of Lightning Ridge, in the northwest of New South Wales and up near the Queensland border. The opals, when you are lucky enough to find them, are generally found in a kaolinitic clay that was the silt of an ancient inland sea. Some opals are opalized fossils from prehistoric vegetation and animals, such as dinosaurs, plesiosaurs, and marine life. There can be several layers of clay, interspersed by layers of sandstone, anywhere from a few feet to perhaps 90 feet from the surface. I had the idea of making some kiln-fired bricks from the clay. Using some coarse material from an old mullock heap near my camp on Phil Herbert’s Rush and a borrowed Cinva ram, I made a few bricks. A local potter fired them in his electric kiln to earthenware temperature (about 1940°F (1060°C)). The firing was not hot or long enough to vitrify the clay and make the bricks strong enough. Despite this, I thought I would try making some pots.

After borrowing a couple of books on pottery from the local library, I built a small updraft kiln using ordinary house bricks. The results were not very good, of course. But, they awakened an interest in making more pots, so I bought a larger gas-fired kiln. I was able to get a lease on a large block of land zoned for industry on the edge of the town. I moved the kiln onto the land and decided to open a pottery there, using the opal clay as my main material.

Habits and Process

My days consisted of building, making cement blocks, and preparing clay. My nights were spent throwing pots on the wheel, often until 1AM or later. I did not have television at the time, so I relied on the radio for news. Late night programs were good—my favorite was A Prairie Home Companion with Garrison Keillor. My studio was open to the public; however, most tourists were more interested in talking about opals and the Ridge than my pottery.

3, 4 View of the entryway and exterior of the showroom train car, now leased to Black Opal Tours.

I started mixing the clay in large plastic garbage bins, stirring slip by hand with a large paddle. The slip was sieved through 60-mesh screens, dried on plaster slabs, wedged by hand, and wrapped in plastic until there was enough to make several pots. This clay was very short, so few pots were made of slabs or coils. Walls of thrown pots were thick and needed turning. I started adding Additive A, as used in the brick industry, which helped gain some plasticity. Later on, I made a blunger from a galvanized-iron 44-gallon fuel drum with a propeller blade, bought a small pugmill, and was able to make several months’ supply of clay, wrap it in plastic, and store it underground. With aging for 3 months or more, the clay improved in plasticity and I stopped using Additive A. The clay was still short when compared to commercial clays, but as my pots were mostly small, that was no problem. If I wanted to make anything taller than 8 inches, it was easier to make it in two pieces and join them. The Giffin Grip for trimming was and still is a most valued tool, as all my pots needed trimming, including a foot rim on even the smallest pots.

I tried clay from probably a couple of dozen of the mining fields. Each varied from field to field in color, shrinkage rate, and silica content. I also tried various temperature ranges, up to 2408°F (1320°C). I made a lot of pots in mid range (cones 4–6); the best results were from stoneware clay. Due to the high silica content of some clays, tension between clay and glaze would cause the glaze to peel off rims and high spots, sometimes even breaking the pot itself.

Unconventional Spaces

I had no family, so I didn’t have to worry about supporting anyone else. Luckily I had saved a few opals for my own pleasure, and as funds were needed, I sold them one by one. I sold my camp out on the fields, and for a while was living in a small caravan, and then another corrugated-iron shack next door to my pottery. My first shop was a small shed with a carport, where I had the wheel and pugmill under cover. This was an ideal place to work on the wheel, with the morning sun in winter and afternoon shade in summer. It was a bit crowded if a bus load of tourists came in. I would do a demonstration for them and talk about the clay. Often there was not one sale to a bus full of tourists, so I charged $2 admission, refundable with any purchase. No one seemed to object. When I would throw at night, I relied on light from one light bulb. Nearly every night, a large green frog came out and sat under the light, waiting for insects to fall.

After about 10 years, I was able to buy an old Red Rattler train carriage from the Sydney urban system. It was mainly for storage under cover, and a small work area for jobs besides pottery. I liked it so much I decided to save up and get another two, one as a residence, and another as a salesroom, which I named The Flying Potsman. I put a veranda alongside the Potsman, with a large sign that read Platform 1. And I was able to put an industrial fence around the whole block of land—nearly an acre in size. Eventually I bought another two carriages. They were a good form of instant building, as they only required a small cement foundation under each end. There are about 6 squares of floor space (10×10 foot each) in each carriage, just under 10 feet wide and about 60 feet long. Sometimes it is an awkward space to work in, but plenty of light filters through the windows. I have no shade roof over the carriages, so in our summers it is uncomfortably hot inside, but in winter they can be pleasantly warm if the sun is shining through the windows.

Inspiration

As there were no potters here from whom I could take lessons, I found Ceramics Monthly and the Clayart listserv to be most valuable sources of inspiration and information. I kept on buying books and subscribing to other pottery magazines from Australia, England, and New Zealand. You could say that my tutors were some of the world’s best potters, and I thank them for putting pen to paper.

When I could afford it, I attended a lot of summer workshops for pottery and other crafts. I treated them as holidays, as I rarely took a break away from the pottery. One advantage was that I could claim they were educational, and therefore a tax deduction. Not that I earned enough to pay income tax, but as a registered business, I had to pay sales tax on sales of pots. Council rates, power, telephone, etc. were also business deductions, as well as a percentage of vehicle costs.

8, 9 Firing the small raku kiln made of firebricks and topped with a lid made of ceramic fiber on steel mesh. Graeme Anderson is pictured on the left in image 8, holding the tongs.

Annual Experimentation

Experimenting was important and as mine was the only work in the kilns, I was not worried about the consequences of things going wrong. Actually, when experiments did not work, they were considered educational. One year, the main experiment was crystalline glazes. I was happy with about 10% of them. I could not work out why the colors were sometimes different than what I expected, until one day, the penny dropped. It was the clays affecting the color of the crystalline glazes. Every pot in the kiln had the same glaze and two pots alongside each other became a happy kiln accident. One shifted in the firing and stuck to the other. One glaze ran a lot, as crystalline glazes generally do, and the other remained stable and did not run at all. The one that ran had beautiful blue crystals on a cream background, while the other had some brownish crystals. The pots were made of different clays, and that was the first time I realized the effect of clays on the glazes.

Another year, the main experiment was ash glazes, starting with a 50/50 clay/ash mix, then adjusting the ratio without adding anything else. Results using ash from oily plants such as pine, eucalyptus, and citrus were okay. A rose bush gave some nice colors, but was dry. Bamboo, being mainly silica, just sat there like coarse sandpaper. Ash from the Mt. St. Helens volcano gave a shiny brown glaze. One pleasant surprise was from the leaves and twigs of boobialla bushes—a common shrub in this area. The ash gave a nice, thick, whitish glaze. A popular item was freshly picked pine needles. I’d put some raw clay pots in the electric kiln, touching each other, and drape the pine needles on their shoulders. After the stoneware firing, the pots were up to 2 inches apart, occasionally with some nice ash glaze runs down the sides. There was also some color from the smoke penetrating the clay. Deciding that this color would look better if it was shiny, I soaked the pine needles in hot water saturated with salt. The fired result was a horrible brown; the needles turned to toffee-like strings holding the five pots in place, stuck together. The salt had eaten right through some of the pots.

The main focus another year was bottles. With friends, there was a lot of fun building a bottle kiln for a one-time performance (no pots were fired). Using sandy soil as a binder, nearly 300 wine bottles were inserted in the kiln wall, with the necks exposed to the heat inside. It was rather a magical night, with the flickering flames shining through the bases of the bottles, a full moon, and, as we realized later, it was Halloween. When the kiln was dismantled, I noted that some very weird shapes resulted, with distorted bottle necks bending down the walls. One port bottle I had suspended from the roof stretched to over a metre (40 inches) in length. I’ve also suspended wine bottles in an electric kiln, generally four in a row. With the right amount of heat, they stretch and also fuse together.

Sauropots and Paper Kilns

At one of the raku firings, local paleontologist Dr. Elizabeth Smith decorated her pot with a drawing of a dinosaur, and coined the word “Sauropot,” a play on the word sauropod, a prehistoric beast that lived in this area, evidenced by opalized fossil remains. The result was so intriguing that, with the collaboration of Jenni Brammall, another local paleontologist, and Zoe King, a local artist, we made and decorated over 100 pots with dinosaurs and other fossils, and held an exhibition. All sale proceeds went to the Australian Opal Centre. As we wanted a stable white glaze, I mixed 100% frit, 5% bentonite, and 5–10% tin oxide. The raku kiln was a box of bricks on the ground and one shelf, holding 8 to 10 pots. The lid was ceramic fiber on steel mesh. The gas passed under the shelf, back over the shelf, with a small hole in the fiber roof so we could see when the glaze melted and could take the pots out before the glaze could run.

11, 12 Paper kiln made using shredded magazines mixed with clay, formed over garden mesh. After lighting a fire on top, the kiln was allowed to burn down overnight.

Another idea I had was to make paper kilns. Using old magazines mixed with clay, I formed the kiln over some garden mesh. I found that if the paper was shredded, the walls were much stronger, as there was more clay mixed with the paper. Similar to pit firing, the unglazed pots (many painted with a salt and copper sulfate mixture) were put in the kiln along with pieces of wood. A small fire was lit on the top, and allowed to burn down overnight. Those pots with interesting marks were given to the various clubs and organizations for trophies or gifts.

In my retirement, I’m writing a booklet on the use of opal clay, and my methods. I also make 100–200 pots a year, mainly for experiments, and do raku firings for friends and for the Australian Opal Centre. We have also held five popular fundraising exhibitions of the Sauropots.

the author Graeme Anderson was born in rural Victoria, Australia, in 1934. After moving frequently as a child, he worked for a bank, and continued to move frequently for work. In 1965, he took a 6-week vacation. When he reached Lightning Ridge, it felt as though he was coming home. He spent holidays there before relocating permanently to mine for opals and make pots. To learn more about Anderson’s pottery and Opal Centre, watch the YouTube videos by IDU Curiosity: www.youtube.com/watch?v=UvFhRdLGxIg and www.youtube.com/watch?v=GsEfRttSp_U.