Getting Started with Ceramic Glazing: Tips and Supplies
Ceramic glazing is one of the most exciting parts of working with clay. A plain bisque-fired piece can become glossy, colorful, metallic, pearlescent, textured, or completely transformed after the right finish and firing.
For beginners, ceramic finishes can feel confusing. What is the difference between glaze and underglaze? When do you use an overglaze? How many coats should you apply? And why do some products need a second firing?
This guide explains the basics of ceramic glazing, underglazes, overglazes, and decorative finishes so you can choose the right products for your next project.
What Is Ceramic Glaze?
Ceramic glaze is a glass-like coating applied to a ceramic piece before firing it in a kiln. During firing, the glaze melts and fuses to the surface of the clay, creating a durable finish.
Depending on the product and firing conditions, glaze can create a glossy, matte, transparent, opaque, textured, or colored surface. In addition to improving appearance, glaze can help make the ceramic surface smoother and easier to clean.
Glazes are typically made from silica, alumina, fluxes, colorants, and other additives. The exact formula determines how the glaze looks and behaves during firing.
Because every glaze line has its own firing range, application method, and compatibility requirements, always follow the instructions on the product label.
Understanding Greenware, Bisque Ware, and Glazed Ware
Greenware
Greenware is unfired clay. It is dry but has not yet gone through its first kiln firing. Some underglazes can be applied to greenware, depending on the product and project.
Bisque Ware
Bisque ware is ceramic that has been fired once but has not yet been glazed. It is porous, which makes it ideal for accepting many glazes, underglazes, and ceramic colors.
Most beginner ceramic projects involve decorating bisque ware, then firing it again after the finish is applied.
Glazed Ware
Glazed ware has already received a glaze coat and been fired. The surface is usually smooth, glossy, or matte depending on the glaze used.
Decorative products such as metallic overglazes, Mother of Pearl finishes, and some china-paint-style products are applied after this stage and fired again at a lower temperature.
Types of Ceramic Color and Finish Products
Underglazes
Underglazes are used for adding color, painting designs, lettering, fine details, and decorative artwork to ceramic pieces.
They are commonly applied to greenware or bisque ware, depending on the specific product. Underglazes give you more control than many standard glazes because they can be brushed, layered, blended, stenciled, sponged, or used for detailed painting.
In many projects, underglazes are finished with a compatible clear glaze to create a glossy, sealed surface. Some underglaze finishes may also be left without a clear glaze when a more matte or natural appearance is desired.
Underglazes are especially useful for:
- Hand-painted ceramic figurines
- Detailed patterns and decorative designs
- Lettering and personalization
- Ceramic ornaments
- Decorative bisque projects
- Layered color effects
Brushing Glazes
Brushing glazes are formulated for application with a brush. They are a practical choice for hobbyists, classrooms, ceramic studios, and home projects because they are easy to control and do not require dipping equipment.
Many brushing glazes are applied in several even coats, allowing each coat to dry before adding the next. Brushing in different directions can help create more even coverage and reduce streaking.
The correct number of coats varies by product, color, and firing range. Some glazes may need two coats, while others may require three or more. Always check the manufacturer’s directions rather than assuming every glaze behaves the same way.
Brushing glazes are a good choice for:
- Bisque ware painting
- Small ceramic projects
- Decorative figurines
- Ceramic ornaments
- Home studio use
- Projects that need controlled color placement
Clear Glazes
Clear glaze is commonly used over underglaze decoration to create a finished, glossy surface while allowing the colors underneath to show through.
A clear glaze can help protect painted designs and give ceramic work a more polished appearance. It is especially useful when you want underglaze details, lettering, or artwork to remain visible after firing.
Always make sure the clear glaze is compatible with the underglaze and firing temperature you are using.
Overglazes and Decorative Finishes
Overglazes are decorative ceramic finishes applied on top of an already-glazed and fired ceramic surface. After application, the piece is fired again at a lower temperature.
These products are often used to add fine details, metallic accents, iridescent effects, and specialty finishes that cannot be achieved with standard glaze alone.
Overglaze products can be especially effective for decorative ceramic pieces, giftware, ornaments, figurines, ceramic trees, and display pieces.
Common decorative overglaze effects include:
- Gold accents
- Platinum accents
- Copper accents
- Mother of Pearl finishes
- Metallic decorative details
- Iridescent finishes
- Specialty decorative colors
Colorobbia overglazes and similar ceramic finishing products are ideal when you want to add a more refined, decorative look after the main glaze firing is complete.
Because overglazes vary widely in application and firing requirements, follow the specific label instructions carefully. Decorative metallic finishes should be treated as decorative unless the manufacturer specifically states that they are suitable for food-contact surfaces.
Mother of Pearl Finishes
Mother of Pearl finishes create a soft, iridescent sheen that can give ceramic pieces a pearly, luminous appearance.
These finishes are often used on decorative ware, figurines, ornaments, gift items, and display pieces. Depending on the product, Mother of Pearl may be applied over an already-glazed piece and then fired at a lower temperature.
The effect can range from subtle and translucent to more dramatic depending on the base glaze, application thickness, and firing conditions.
Metallic Overglazes
Metallic overglazes can add a high-end decorative effect to ceramic work. Gold, platinum, and copper finishes are commonly used to highlight raised details, rims, lettering, trim, and decorative patterns.
These finishes are often applied with a fine brush after the ceramic piece has already been glazed and fired. The piece is then fired again according to the product’s recommended overglaze firing instructions.
Metallic overglazes work especially well on:
- Ceramic figurines
- Decorative plates
- Ceramic ornaments
- Holiday projects
- Ceramic trees
- Personalized giftware
- Accent pieces and display items
Essential Ceramic Glazing Supplies
Bisque-fired ceramics: Most glazes and ceramic colors are applied to bisque ware. Make sure the piece is clean, dry, and free of dust before you begin.
Ceramic glazes and colors: Choose glazes, underglazes, overglazes, or specialty finishes based on the look you want to achieve and the type of firing available to you.
Brushes: Flat brushes work well for larger areas, fan brushes can help with blending and texture, liner brushes are useful for lettering and fine detail, and round brushes offer controlled color placement.
Sponges: Sponges are useful for cleaning bisque ware, removing excess product, softening painted edges, and applying color to textured surfaces.
Wax resist: Wax resist is often applied to the foot ring or bottom of a ceramic piece to help keep glaze off areas that may touch the kiln shelf.
Glaze thinner or medium: Some ceramic finishes may need to be thinned or adjusted before application. Use only a compatible thinner or medium recommended for that specific product line.
A clean workspace: Dust, oils, and debris can interfere with glaze adhesion and create defects after firing. Keep your work area clean and make sure the ceramic piece is free of dust before applying any finish.
Step-by-Step: How to Glaze a Ceramic Piece
Step 1: Clean the Bisque Ware
Wipe the ceramic piece gently with a clean, damp sponge to remove dust and debris. Allow it to dry completely before applying glaze or color.
Dust can prevent the finish from adhering evenly and may cause rough or patchy areas after firing.
Step 2: Plan Your Design and Finish
Before applying color, decide which products you will use and in what order. A project may use underglaze followed by clear glaze, brushing glaze applied directly to bisque ware, or a metallic overglaze added after the original glaze firing.
Testing new combinations on a small sample tile is always a good idea before applying them to a finished project.
Step 3: Apply the Ceramic Finish
Stir glaze thoroughly before use because heavier materials can settle to the bottom of the jar.
Apply the product according to its label instructions. Many brushing glazes require multiple even coats, but the correct number of coats depends on the specific glaze line, color, and firing range.
Allow each coat to dry before applying the next. Avoid applying thick, uneven layers that could run during firing.
Step 4: Keep the Bottom Clean
Before firing, inspect the foot ring and bottom of the piece carefully.
Remove any glaze from areas that will touch the kiln shelf. A damp sponge, scraper, or other appropriate cleanup tool can help remove excess product.
This step is important because glaze on the bottom can melt and permanently fuse the ceramic piece to the kiln shelf.
Step 5: Fire According to Product Instructions
Fire the piece according to the temperature and schedule recommended for the specific product you used.
Do not assume all ceramic finishes fire at the same temperature. Standard glazes, underglazes, clear glazes, metallic overglazes, and Mother of Pearl finishes may all require different firing ranges.
When firing glazed ware, make sure pieces do not touch each other. Glazed surfaces can fuse together in the kiln.
How to Apply Overglazes and Metallic Finishes
Start With a Clean Glazed Surface
Make sure the glazed piece is clean, dry, and free of fingerprints, dust, and oils before applying a decorative overglaze.
Apply Carefully
Use a fine brush to apply overglaze only where you want the decorative finish. Metallic products can be used for trim, lettering, dots, borders, raised textures, and accent lines.
Apply evenly and avoid overworking the finish.
Fire at the Recommended Lower Temperature
Overglazes typically require a lower firing temperature than the original glaze firing. Follow the manufacturer’s label for the correct firing schedule.
Do not fire metallic finishes at standard glaze temperatures unless the product specifically instructs you to do so.
Common Glazing Mistakes and How to Avoid Them
Applying Glaze Too Thin
Glaze that is too thin may look weak, patchy, dull, or uneven after firing. Use the recommended number of coats and apply them evenly.
Applying Glaze Too Thick
Glaze that is applied too heavily can run during firing, create drips, or damage the kiln shelf. Follow the product directions and avoid adding extra coats simply to make the color look darker before firing.
Forgetting to Clean the Bottom
Glaze on the foot ring or bottom of the piece can fuse it to the kiln shelf. Always inspect the bottom before loading the kiln.
Mixing Incompatible Products
Not every glaze, underglaze, overglaze, or specialty finish is designed to work together. Test unfamiliar combinations on sample tiles before applying them to a completed project.
Firing at the Wrong Temperature
Firing temperature matters just as much as application. A product fired too low may look dull or underdeveloped. A product fired too high may run, burn out, change color, or lose its intended finish.
Always use the firing temperature recommended for the specific product.
Treating Decorative Finishes as Food-Safe
Metallic overglazes, Mother of Pearl, and other decorative finishes may not be suitable for food-contact surfaces unless the manufacturer specifically states otherwise. Use these products for decorative ceramic work unless you have confirmed the intended use from the product instructions.
Shop Ceramic Glazes, Overglazes and Supplies
Ready to start your next ceramic project? Explore our selection of ceramic glazes, underglazes, Colorobbia overglazes, metallic finishes, Mother of Pearl products, brushes, thinners, and ceramic decorating supplies.
Whether you are painting bisque ware, adding a clear glaze finish, creating a custom ceramic tree, or adding gold, platinum, copper, or pearlescent accents to a decorative piece, you can find the supplies you need to bring your idea to life.
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