Pottery Terms Every Ceramic Artist Needs to Know

Pottery is an ancient and captivating art form that involves shaping and firing clay to create beautiful, functional objects. Whether you're new to the world of ceramics or looking to expand your knowledge, it's essential to grasp some fundamental pottery terms. 

These common pottery terms help you understand the techniques, tools and processes involved in this ceramic process. From the types of clay used to the various stages of creating a ceramic piece, this pottery glossary will provide you with a solid foundation to begin your pottery journey with confidence.

Bat

A bat is a flat, usually circular piece of material placed on the wheel head of a pottery wheel. Bats come in various sizes and materials to serve as a removable surface on which pottery pieces are created and worked. 

Potters sometimes throw their clay on a bat, allowing them to shape and work on the piece while keeping it easy to remove and transport without deforming it. Additionally, potters can put their thrown pieces on bats with specialized surfaces to trim or smooth the surfaces of their work.

Bisqueware

Pottery that has been fired once in a kiln at a relatively low temperature, typically at a range of around 1,700 to 1,900 degrees Fahrenheit (930 to 1,040 degrees Celsius). 

This initial firing hardens the clay and removes most of its moisture, making it solid and porous but still porous enough to readily absorb glaze when it is applied. Bisqueware serves as an intermediate stage in pottery making, after which it can be glazed and fired again at a higher temperature to create the final, glazed ceramic piece.

Bisque Cone

Bisque cones are designed to bend and deform at a precise temperature, which corresponds to a particular level of heat treatment. As the temperature in the kiln rises, the bisque cone softens and bends. 

The angle at which it bends is an indicator of the temperature reached in the kiln, allowing potters to ensure that the bisque firing has reached the desired temperature for their clay and glaze combination. 

This information helps potters achieve consistent results and avoid underfiring or overfiring their pottery. The specific cone used may vary depending on the type of clay and glaze being fired, and potters often select cones that match their firing requirements.

Bisque Firing

The initial firing process in pottery, during which greenware (unfired clay objects) is placed in a kiln and heated to a specific temperature, typically in the range of 1,700 to 1,900 degrees Fahrenheit (930 to 1,040 degrees Celsius). 

This firing transforms the clay into bisqueware by removing most of its moisture, making it hard and durable and more stable for handling and glazing. Bisque firing also prepares the pottery for the application of glaze, which is typically added in a subsequent firing, known as the glaze firing.

Bone Dry 

Bone dry is a stage in pottery and ceramics when clay has dried to its most fragile and unfired state, typically after air drying for an extended period. At this point, the clay has lost nearly all of its moisture, making it very brittle and susceptible to cracking or breaking. 

Bone-dry clay is ready for its first firing, often referred to as the bisque firing, in a kiln to remove any remaining moisture before it can be glazed and fired again for the final finish.

Carving

The process of incising or cutting decorative designs, patterns, or shapes into the surface of a clay object. This technique is often used to add intricate details, texture, and visual interest to pottery pieces, enhancing their aesthetic appeal and creating unique, personalized designs. 

Carving tools remove clay material and create the desired patterns or relief on the pottery's surface.

Ceramic Bisque

Ceramic bisque refers to pottery that has undergone the initial firing, typically a bisque firing, but has not yet been glazed or fired again in a glaze firing. At this stage, the clay has been transformed into a hard, porous and unglazed ceramic material. 

Ceramic bisque is often used as a canvas for decorative work, such as painting or adding additional clay elements, and is ready to be glazed to create the final, finished ceramic piece.

Ceramic Decals

Ceramic decals, also known as ceramic transfers, are pre-designed, printed images or patterns that can be applied to the surface of ceramic or pottery objects. 

These decals are typically made from specially formulated ceramic pigments and are transferred onto the pottery piece before it undergoes the final glaze firing in a kiln. During the glaze firing, the ceramic decals fuse with the glaze, becoming a permanent part of the finished piece. 

Ceramic decals are commonly used to add intricate, detailed designs, illustrations or personalized decorations to pottery, making them a versatile tool for creating unique and visually appealing ceramic artwork or functional pieces.

Ceramic Studio

A ceramic studio is a dedicated workspace or facility equipped with the tools, equipment and materials necessary for creating pottery and ceramics. It is a place where artists can engage in various stages of the ceramic-making process, including clay preparation, throwing or hand-building, glazing and firing. 

Ceramic studios often provide access to pottery wheels, kilns, worktables, storage for clay and tools, and other resources needed for pottery creation. These spaces are used for both artistic exploration and the production of functional and decorative ceramic pieces. 

Ceramic studios can be found in schools, community centers, and art institutions or operated as independent studios by individual artists. Keep in mind that keeping your studio clean is crucial for health, safety and creativity. 

Clay 

The primary material used in pottery. Clay is a natural, malleable material composed of finely ground minerals and organic matter. It comes in various types, such as earthenware, stoneware and porcelain, each with its own properties. 

Coil Building

Coil building is a pottery technique that involves creating ceramic forms by rolling out long, snake-like coils of clay and then stacking and shaping them to build up the desired shape. 

These coils are usually blended or joined together to create solid walls, allowing potters to construct a variety of vessels and sculptures with a unique, textured appearance. Coil building offers opportunities for both structural creativity and decorative embellishments in pottery.

Crazing

A network of fine cracks, known as crazing, can develop on the surface of a glazed ceramic object. These cracks typically appear after the piece has been fired and as it cools down. Crazing is often caused by the way thermal expansion rates differ between the glaze and clay. 

While crazing can create an interesting aesthetic effect, it can also compromise the functionality of pottery, especially if it affects the watertightness of the glaze.

Glaze

Glaze is a liquid mixture typically made from minerals and colorants that is applied to the surface of pottery or ceramics before firing in a kiln. When fired at high temperatures, the glaze melts and forms a glassy, protective and decorative coating on the surface of the pottery, enhancing its appearance and making it more durable, waterproof and food-safe. 

Glazes come in various colors and finishes, allowing potters to achieve a wide range of artistic and functional effects on their ceramic creations.

Glaze Firing

Glaze firing is the second firing process in pottery, following bisque firing. During a glaze firing, ceramic objects (typically bisqueware) are placed in a kiln and heated to a higher temperature, typically within the range of 1,800 to 2,400 degrees Fahrenheit (980 to 1,320 degrees Celsius). 

The purpose of this firing is to melt the glaze coatings applied to the pottery, creating a glossy and decorative surface. Glaze firing is essential for making the pottery both aesthetically pleasing and functional. It seals and protects the clay, making it impermeable to liquids and enhancing its durability.

Glaze Recipe

A glaze recipe in pottery and ceramics refers to a specific formula or combination of raw materials used to create a glaze mixture. This recipe outlines the precise amounts and types of ingredients, including various minerals, oxides and other compounds, needed to produce a particular glaze with specific characteristics, such as color, texture and surface finish.

Glaze recipes are essential for potters and ceramicists to replicate and experiment with different glaze effects and results. These recipes can vary widely, allowing artists to achieve a diverse range of visual and functional outcomes in their pottery pieces. 

Glaze recipes are documented and shared among the pottery community, enabling artists to explore and create unique glaze effects while maintaining consistency and predictability in their work.

Glaze Ware

Pottery or ceramic objects that have undergone the glaze firing process. In this final stage of pottery creation, glaze is applied to the surface of the ceramic piece the piece is then fired in a kiln at a high temperature. 

During this firing, the glaze melts and forms a smooth, glossy and decorative coating on the pottery. Glaze ware is known for its colorful, glass-like finish, which enhances the aesthetic appeal of the pottery and makes it functional. It becomes waterproof and resistant to staining or absorption of liquids. 

Glaze ware can include a wide range of ceramic objects, such as plates, bowls, vases and sculptures.

Greenware

Greenware is pottery that is in its raw, unfired state after being shaped and formed but before undergoing any firing processes. 

At this stage, the clay is still wet and malleable, but it has not yet been bisque-fired or glazed. It is in this state that potters can add intricate details, textures or decorations to the pottery before it goes through the firing process

Greenware is delicate and must be handled with care. It can be easily deformed or broken. 

Grog

Grog is a pottery and ceramics material made from crushed, fired clay that has been ground into granules of various sizes. These granules are then added to clay bodies to modify their properties and improve their characteristics. 

Grog stabilizes and strengthens clay bodies, reducing their tendency to crack or shrink during drying and firing. It’s available in various particle sizes, from fine to coarse. Potters select the appropriate type and amount based on the specific properties they want to achieve in their clay body.

Kiln 

A kiln is a specialized high-temperature oven or furnace used in ceramics and pottery to heat and fire clay objects. Kilns are designed to reach and maintain precise temperatures, allowing the clay to undergo chemical and physical changes, ultimately transforming it into durable and finished ceramic pieces.

Kiln Furniture

Kiln furniture, also known as kiln shelves and kiln furniture kits, refers to a collection of heat-resistant refractory materials and supports used inside a kiln during the firing process of pottery and ceramics. 

Kiln furniture is typically made from silicon carbide, cordierite or alumina, which can withstand the extreme heat and thermal cycling of the kiln. 

Leather-hard

A stage in pottery and ceramics when clay has dried for about one day and still carveable. Too moist clay doesn’t carve well. Ideal dryness for carving is like a chocolate bar or Parmesan cheese. 

Rib

A rib is a tool made of wood, metal or plastic, shaped like a flat, elongated paddle or spatula. Potters use ribs to shape, smooth and refine the surface of their clay creations. 

They can be used both on the interior and exterior of pottery pieces, helping to achieve desired forms, remove excess clay, and create smooth, uniform surfaces. Ribs come in various shapes and sizes, and the choice of rib depends on the specific pottery technique and the desired result.

Score and Slip

To score means to make shallow cuts or scratches on the surface of the clay where you want to join two pieces. These cuts create a rough texture that helps the clay pieces adhere to each other. 

Slip is a liquid mixture of clay and water, creating a paste-like consistency. It acts as an adhesive. After scoring both clay surfaces to be joined, you apply slip to one or both of them before pressing them together. The slip fills the scored grooves, creating a strong bond as it dries.

Slab Building

A pottery technique that involves creating ceramic objects by rolling out flat, even sheets of clay and then cutting and assembling these sheets to construct the desired form. It often involves the use of templates or molds to achieve precise shapes and sizes. 

Slab building is a versatile method that allows potters to create a wide range of pottery forms, from simple plates and tiles to complex sculptures and functional vessels.

Sanding

Sanding in pottery is the process of smoothing and perfecting the surface of a clay object, typically using abrasive materials like sandpaper or pads. It helps to eliminate imperfections and achieve a smooth finish, enhancing both the aesthetics and functionality of the pottery.

Sgraffito

Sgraffito is a decorative pottery and ceramic technique that involves carving or scratching through a colored slip or underglaze on the surface of a clay object to reveal the contrasting clay body underneath. The term "sgraffito" is derived from the Italian word "sgraffiare," which means "to scratch." 

Using the sgraffito technique, an artist first applies a layer of slip (a liquid clay mixture) or underglaze in a contrasting color to the surface of the pottery. Once the slip or underglaze is applied and dried but still slightly damp, the artist uses sgraffito tools to carefully scratch or carve designs, patterns or images into the surface. The scratched areas reveal the natural color of the clay body underneath.

Shrinkage

The reduction in size that clay experiences as it dries and is subsequently fired in a kiln. This natural occurrence happens because clay particles compact and water evaporates during the drying and firing processes, causing the clay to contract or shrink. 

Shrinkage is an important factor for potters and ceramicists to consider when designing and creating pottery, as it affects the final dimensions and proportions of the ceramic pieces. 

Understanding and accounting for shrinkage is crucial to achieving the desired size and shape of finished pottery. Our shrink ruler is an easy-to-use tool to make this process easier and ensure consistency among your pieces.

 

Trimming

Trimming, in pottery and ceramics, is the process of refining and shaping the bottom and outer edges of a pottery piece after it has partially dried and become leatherhard but before it is completely dry. 

This is typically done using a trimming tool to remove excess clay and create smooth and even surfaces, including the bottom, for a vessel. Trimming not only adds a functional element to the pottery but also enhances its aesthetic appeal and overall balance.

Throwing 

The skilled process of shaping and forming clay on a potter's wheel. It involves centering a lump of clay on the wheel and then using skilled hand and foot movements to create objects with symmetrical and consistent shapes, such as bowls, cups and vases.

Underglaze

Underglaze is a type of ceramic decoration or colorant that is applied to the surface of pottery before it is glazed and fired. Underglazes are formulated as liquid or powdered mixtures and come in various colors. 

During the firing process, underglazes fuse with the clay body, creating permanent, vivid and often detailed designs that are preserved under the transparent or translucent glaze layer. Underglazes offer artists a wide range of possibilities for adding color and intricate decoration to their ceramic creations.

Wedging

Wedging involves kneading and manipulating a piece of clay to remove air bubbles, ensure uniform consistency and improve its plasticity. This process is typically performed on a flat work surface and involves pressing, folding and rotating the clay to create a smooth, workable material that is ready for shaping and forming into pottery pieces. 

Wedging helps prevent structural weaknesses and imperfections in the clay and ensures a more successful and even outcome in the pottery-making process.

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If you have any questions about our tools or any of these pottery terms, we’re here to help. Leave a comment or get in touch with our team on Facebook and Instagram. We can’t wait to see what you’re creating.