In the world of pottery, where creativity and craftsmanship converge, some artists are not just molding and glazing their clay, but creating their own unique surface treatments. Experiments with glazes lead these artists down rabbit holes to places where earthy elements transform into never-before-seen hues and textures.
The Center for the Visual Arts in Wausau (CVA-Wausau) is spreading the joys of glaze-craft in central Wisconsin. Opened in 1976 and now located in a historic arts block in Wausau’s downtown, CVA-Wausau is a dynamic and inclusive space for both emerging and established artists. The Center takes pride in its education program, which offers workshops, classes, and lectures for both aspiring and seasoned artists.
Mara Mullen, Director of Education, finds that students in CVA-Wausau’s pottery classes come in “focused on the clay body—making a mug, a bowl, a vase—rather than thinking about how it might be glazed. They’ve never been exposed to this aspect of ceramics,” she said. “They look at our glaze board and they can be a little overwhelmed.” The studio, where potter Ron Hay has been artist-in-residence since the 1990s, currently produces 35 custom glazes. “It’s like cooking,” Hay said. “There are thousands of recipes. Potters share them, and there are books full of them.” But he noted that outcomes can still be unpredictable. “A lot of times, a recipe doesn’t work when you mix it up, because your chemicals came from a different part of the country than the than the other ceramicists.” A slightly different molecular composition can yield a quite different result. But, said Hay, “You don’t have to be a chemist—you learn to adjust recipes through trial and error.” Because most students want to make functional ware, almost all of Hay’s house-made glazes are designed to be food-safe.
The Science Behind the Surface
People unfamiliar with ceramics may have admired the colorful surfaces of pottery without giving a thought to the “how” and “why” of their glazes. Glaze is a coating applied for both aesthetic and practical purposes, designed to adhere to a fired ceramic object. Glaze attributes vary widely, from glossy to matte, translucent to opaque, glassy-smooth to textural. Its main components are silica, which forms the glassy surface; flux that lowers the melting point to improve adherence; and alumina to stabilize the glaze. Silica comes from quartz, flux is often feldspar or boron compounds, and alumina is an element derived from clay. Additionally, pigments play a crucial role in ceramics, contributing to the rich palette of colors seen in glazed pieces. These finely ground substances are added to the glaze mixture or to the clay itself, to introduce hues and variations. Part of ceramic art’s appeal is the earth-bound nature of the materials involved.
Glaze components react in a kiln during the firing process. As the temperature rises, the glaze transforms from a powder into a molten, glassy substance. The right balance of silica, flux, and alumina, along with additional elements for color and texture, determines the final appearance of the glaze. Understanding this basic chemistry provides a practical foundation for ceramicists to experiment with different formulations to achieve specific effects on their pottery.
Beyond the three main components, a variety of other materials can be added depending on the artist’s vision for the piece. For example, colors and textures can be customized, and glazes can be made to move in certain ways to achieve effects such as cracking, foaming, or dripping. A glaze’s behavior and appearance depend on how it is fired—the same glaze may turn out differently with different temperature, timing, and the atmosphere in the kiln. Adding or reducing oxygen or introducing wood, salt, or other materials will also affect a glazed object’s ultimate appearance.
Beginners can get started in ceramics with just an introductory level of knowledge, or choose to advance as far as they like; the range of knowledge among working ceramic artists is broad. Some, however, who fall down the rabbit hole and discover the intriguing world of pigments and glazes, are driven to learn the chemistry behind this wonderful alchemy.
David Harper, an interdisciplinary artist living near Racine whose work is in the collections of the John Michael Kohler Art Center and The Museum of Wisconsin Art, began working with clay when he realized he was using non-clay materials to create objects that imitated ceramics. “At any point, you can choose to stop or go deeper. Knowing the basics is important, like how hot to fire certain things to achieve certain effects. Then people might get into making their own glazes, achieving effects nobody has ever seen before.”
Some artists introduce pigments into the clay itself, not just the glaze. Michael Ware creates abstract ceramic sculptures and teaches ceramics at the University of Wisconsin-Milwaukee. He began working with stains and pigments to express his interest in “this geological world,” he said. “It was disappointing whenever I broke a little bit off a sculpture and it was white inside. Glaze is just on the surface, whereas when I color the clay, it has color the whole way through—like a rock.”
But, artists advise, do not start making glazes until you know how to do so safely. Understanding material hazards and proper use of studio equipment and tools is critical. Potters need to minimize aerosol particles and exposure to toxins. That means, when mixing clay and glazes, always wear a respirator and work with good ventilation systems; never eat or drink in the studio; wear safety glasses and gloves. Wipe down work surfaces and mop floors. Some glaze ingredients, like barium and lithium, yield beautiful effects but are toxic. The toxicity can range from mild skin irritation to causal factors in cancer. Kilns have their hazards, too. Loading and unloading heavy pieces can cause injury. While firing, fumes are present. It is important to avoid the area and/or use good ventilation and a respirator. Check that no combustible materials are located near a kiln before every firing. When producing functional ware, such as plates and mugs, use only food-safe glazes. Safety guidelines are reassessed regularly—otherwise, we might still use lead in glazes! Check for current information before working with glazes.
Why Go Down the Rabbit Hole?
Potters choose to make their own glazes for several reasons including cutting costs, developing greater skill with their medium, and controlling the environmental impact of their work. But the reason most cited for diving into glaze-making is to achieve a specific creative vision.
The cost of commercial glazes often drives beginning potters to make their glazes. Simply setting up a studio requires an initial investment that can be steep even before purchasing dozens of glazes, which frequently cost more than twenty dollars a pint. Mixing glazes requires only common kitchen tools like a scale, mixer, and measuring utensils, and the ability to follow a recipe.
The educational value of learning to formulate and test glazes is undeniable; potters deepen their understanding of materials, chemistry, and firing processes through glaze-making. Mullen said, “With beginning students, we steer them towards our most predictable glazes because they put so much effort into making these precious objects. If they fail, it can turn students away from ceramics in general.” Ceramic-making involves not only experimentation but also failure. Learning to troubleshoot the causes of failures is important to the process.
Increasingly, ceramic artists are considering the environmental sustainability of their art form. Clays and the chemicals used in glazes are mined all over the world. Materials mined in one place are frequently shipped to distant locations for processing and then shipped again to the point of sale. Ware said, “I’ve become more aware of the environmental impact of ceramics and the environmental impact of all that transport.” Historically, potters lived close to sources of clay and mined the clay themselves. Today some potters are working with “wild clay,” finding raw materials nearby and screening out impurities to create workable clay.
Madison-based potter and ceramics teacher Joanne Kirkland makes porcelain sculptural pieces inspired by the pottery of the southwestern United States, Mexico, and Japan. She primarily uses Grolleg, a blended china clay from England, where some Grolleg mines are now depleted. Kirkland said, “I recently started thinking I should use more local materials, what with climate change and the impact of transportation.” She has begun experimenting with wild clay herself. So has Ware, who likes using the local pale-gold clay that, made into bricks, gave Milwaukee the name Cream City. From the sustainability of the raw materials, through managing the risks of the more dangerous chemicals in glazes, to the disposal of waste materials, potters are increasingly choosing materials and processes for their environmental sustainability.
Artistic expression is the foundation of every aspect of a ceramic artist’s work and the dominant reason for making glazes. Color palettes, surface effects, and where a particular idea for a piece fits on the spectrum from functional to sculptural all factor in, driving choices about pigments and glazes. Experimentation is an integral part of that process, as artists tweak formulas, test new combinations, and push the boundaries of traditional glaze recipes to achieve unique results. Harper said, “Every ceramicist I know has libraries of test tiles where they have added grain after grain of a certain mineral to change a pigment or change how a glaze flows. Control is the draw for a lot of people.”
And yet control must be balanced with openness to serendipity. Scott Draves of Door Pottery in Madison teaches beginning and continuing students through local community programs. “I conceive of a glaze for each piece before throwing it, a process that only a small percentage of potters do. The best work comes out of the surprises and mistakes I make.”
Rachel Imsland, a potter who serves on the board of the Madison Area Potters Guild, said, “I have to remind myself to have no expectations, because when I expect a pot to look a certain way it won’t. You always need to be open and be ready for a surprise.” Imsland set up a home studio during the pandemic. She began making glazes because she missed the ones available at the Midwest Clay Project, a community clay studio in Madison, where she had worked prior to COVID. At first, Imsland saw making her own glazes as a huge hurdle. “As a beginner, you just want to think about making pots. Somebody else, please make the glaze. But with practice, you find, it’s fun!”
Artists Speak
Custom creation of glazes and pigments is taking place across Wisconsin in schools, universities, community spaces, and artists’ studios. Some are working in traditional techniques and some are digging deeper with experiments that erase the line between the clay body and the glaze.
Scott Draves creates functional ware inspired by the Arts and Crafts movement. This international trend in the decorative arts emerged as a reaction against the industrialization of the late 19th century. Its proponents championed craftsmanship, simplicity, and a return to traditional techniques in which the maker’s hand is visible. Draves recreates that style with pigments and glazes he customizes to mimic the originals, minus the deadly lead content used in the glazes of a century ago. Like Draves, many of today’s ceramic artists are drawing inspiration from the ethos of the Arts and Crafts Movement, finding a potent source of creativity in its rejection of mass production and celebration of the handmade.
Kirkland took a ceramics class while studying fashion design in college, where she fell in love with the physical, tactile, experience of clay. “What drew me in was learning how to throw on the wheel; learning how to center was the hardest thing,” she said. “You have to be pretty centered yourself to do it. When you learn to use your body, that is a very magical experience.” Over the decades, she has evolved from an interest in functional objects to a focus on more metaphorical sculptural vessels. Throughout, her objects’ surfaces have been decorated with geometric representations of natural phenomena. Ancient pottery fascinates her; “I enjoy residing in a continuum of thousands of years of tradition,” said Kirkland. “It’s been a constant evolution and exploration, a dialogue with clay and glazes.”
CVA-Wausau’s Mullen started out primarily sculptural in her art, but after her teaching experience she now leans toward functional ware. “It’s a joy to create things I need and would like to use. But I do still love sculpture. I love rethinking the vase, rethinking the mug—how can I bring sculptural elements to these functional works?”
Harper considers himself not a ceramicist, but an artist who uses clay as part of his vocabulary. Originally from Toronto by way of the Nova Scotia College of Art and Design, he spent two seasons as the Kohler Arts and Industry Artist in Residence in winter 2012 and 2014. “There is a beautiful symbiotic relationship there,” he said. “Working in this very utilitarian environment, watching the grace, the dance of these factory associates working with the same material I use—it still affects the way I work in the studio, based on their model of efficiency.” Harper’s installations are cross-disciplinary and employ both traditional and nontraditional materials. “I make these small worlds that are so bizarre but are grounded by materials I choose because of their familiarity,” he said. “I choose colors and surface textures that are nostalgic.”
Christina West is an Associate Professor in Ceramics in the Art Department of the University of Wisconsin-Madison. While teaching an introductory ceramics class, West found herself growing enthusiastic about what glaze can do that other materials can’t. “In trying to get the students excited about it, I sold myself on it,” she said. “You can change the qualities of an individual glaze, but when you put two or three glazes on top of each other, they do unpredictable things.” She explores the push-pull between unpredictability and replicability. “I’ve found a sweet spot where I know in general what’s going to happen, but I can’t predict exactly.” Her work is sculptural and frequently multi-media; her installations have explored fragmenting human forms and creating surface textures that contemplate mortality. “I feel very much like a painter when I’m glazing,” West said. “I’m thinking about marble, but I want a fleshiness to show through so it’s more humanistic.”
At the Dripping Edge of Experimental Technique: Gloops and Clazes
Ceramic artists are embracing the expressive and organic nature of their materials and processes, part of a movement sometimes called “action claying” that exploits the alchemy inside the kiln. Some are using “gloop” glazes, a term coined to describe thick, viscous, unpredictable surface treatments, which represent a departure from the traditional, more controlled glazing techniques. Heat determines whether clay and glazes behave like solids, liquids, or even gasses. Gloop work is characterized by drips, dynamic textures, and vibrant colors. Artists are drawn to the serendipity inherent in a process that leaves so much to the kiln’s environment to complete.
One of West’s graduate students, Morgan Baldinelli, is part of this trend, creating clay bodies with voids that she fills with gloop, then suspends in the kiln so that drips pour from inside the pieces when the kiln reaches its highest temperature. “I’m personally fascinated with glazes and how surface texture occurs,” she said.
“The only thing connecting the two gray pieces is the gloop material. It took a bit to figure out how to suspend it in the kiln so that it would flow as I wanted.”
Ware was drawn to ceramics once he discovered the parallels between the ceramic process and certain geologic processes; in both, materials combine through heat, pressure, and time. Bringing that into his vision for his pieces, he said, “I’m not so much trying to replicate what forms look like but more so to bring out their energy.” Seeking to express energy with color, he began adding pigments to clay when he noticed the colors were even more vibrant than glazes.
Recently Ware has begun experimenting with the sculptural qualities of glazes. “I call it “claze” because it’s kind of a mixture of clay and glaze,” he said. “I play a lot with that boundary between the two. I try to create some parameters to then experiment within and solve problems.” In some of Ware’s work, he uses claze—and the kiln’s heat—to fuse in the kiln small individual elements built of clay to make larger sculptural pieces. In others, he buries claze in boxes filled with sand, and then excavates the resulting pieces after firing. “That came from my interest in geology,” he observed.
This trend in ceramic arts embraces spontaneity and the imperfections that arise in the creative process. It celebrates the unplanned and the unrestrained. It is only natural that counter-trends will emerge as they always have, pushing the boundaries in different directions. We may next see a deliberate move away from the exuberance of gloop glazes toward minimalist and refined aesthetics, where artists opt for cleaner lines and precise glazing techniques.
Where Will Tomorrow’s Glaze-Makers Learn Their Craft?
A journey down the rabbit hole of custom-made pigments and glazes leads to something akin to the extremes at the earth’s core, where intense heat applied to earth elements produces a magic array of rocks and minerals. One wonders what tomorrow’s ceramic artists will produce, and how they will learn their craft.
Draves, who teaches pottery through Madison School-Community Recreation (MSCR) and at Madison College, observed, “Everything used in ceramics is essentially broken-down rock. The first time students get their hands on that, they just love the feel of the material. Nine out of ten will want to try another class.” But will there be classes for them to enroll in?
While teachers report that classes fill immediately, some schools and universities under pressure from tight finances have closed pottery teaching studios and even ended arts instruction entirely. At CVA-Wausau, Mullen said, “We’re lucky because we have wonderful arts educators within our school system. But I know that access to ceramics equipment and facilities isn’t the case elsewhere, especially in more rural areas. We try to spread what we do here as far into the state as we can.” Rural schools in central Wisconsin bring their students into Wausau for immersion days offered at the Center’s pottery studio.
The Wisconsin Department of Public Instruction’s data indicates that student enrollment in ceramic arts programs declined from 32 percent in 2019 to 28 percent in 2021, while overall arts enrollment dropped by 10.7 percent in that timeframe. To lose more arts programs, especially in ceramics, would be a blow.
Ware observed, “Ceramics inherently creates communities because it’s hard to do alone. Filling and firing a kiln can be very laborious. Also, potters work long hours in a space shared with other people.” At a time when social isolation has been identified as a national health threat and young people are experiencing worsening mental health, arts programs offer a counter-balance. Kirkland said, “When I started teaching at Madison College, so many students told me, ‘This is like therapy.’”
But perhaps the most important reason to call for the continuation of arts education programs is the least tangible. “When students ask me what they can do with a ceramics degree,” Ware said, “I tell them, you’re qualified for everything and nothing. You are learning problem-solving skills, and those are invaluable throughout your life.”
