What Can I Use To Make Clay Glossy?

Clay can be made glossy through a variety of techniques that add sheen and luster to the surface. The glossiness or shine highlights the form, enhances the color, and gives depth to ceramic pieces made of clay. A glossy surface is smooth, reflective, and light-catching compared to an unfinished clay surface which tends to be matte and porous.

There are several ways to make clay glossy depending on the type of clay, the desired effect, and the stage of production. Common techniques include applying sealers, resins, glazes, oils, and wax which fill in pores and create a glass-like coating. Burnishing, polishing, and adding mica powder physically smooth and compress the clay surface to reflect light. The purpose of creating a glossy clay surface is primarily decorative and aesthetic.

This overview covers the most popular options for making clay glossy from start to finish. Each material and technique has its own advantages and achieves a slightly different look. With some trial and error, clay artisans can find the right glossy finish to suit their project goals and artistic vision.

Sealers

One of the most popular ways to make clay glossy is by applying a protective sealer. Sealers form a coating over the clay that provides a barrier against moisture, dirt, and stains. When dry, most sealers impart a glossy sheen. Some of the top sealers for achieving a glossy clay finish include:

Acrylic Sealers – Acrylic sealers are water-based and provide a clear gloss finish. They are easy to apply with a brush and dry fast. Acrylic sealers work well on polymer clay, air-dry clay, and baked clay.

Polyurethane – Polyurethane is a durable sealer that dries to a thick glossy coating. It provides excellent protection for items used outdoors. Polyurethane can yellow over time so is best for light colored clays.

Wax Sealers – Wax based sealers like paste wax provide a soft lustrous finish. They are easy to apply and buff out. Wax sealers need reapplied periodically as the wax wears off. Wax works especially well for a glossy look on jewelry and decorative clay items.

Varnish – Varnish such as polyurethane varnish forms a clear, glossy film over baked clay. It provides a glass-like surface that resists scratches. Varnish requires proper ventilation during application as fumes are strong.

Casting Resins

Casting resins are commonly used to coat polymer clay sculptures or pieces to give them a glossy, glass-like finish. The two main types of casting resins for polymer clay are polyester resin and epoxy resin.

Polyester resin is often the cheaper option. It cures quickly, but can be messy to work with and prone to bubbling. Epoxy resin is more expensive, but has a lower viscosity so it self-levels nicely and doesn’t bubble as much. Epoxy resin also provides a higher gloss finish.

To apply a casting resin coating to cured polymer clay:

• Ensure the clay piece is thoroughly cured, clean, and dry.
• Mix the resin according to manufacturer’s instructions.
• Apply resin in thin layers using a disposable brush or plastic spreader.
• Allow each layer to cure fully before adding the next.
• Sand lightly between coats for a smooth finish.
• Apply 2-5 layers for best results.

Casting resins provide a durable, flawless glossy coating for polymer clay. Just be sure to work in a well-ventilated area.

Glazes for Gloss on Clay

Glazes are specially formulated glass-like coatings that can be applied to bisque fired or greenware clay to give it a glossy finish. Glazes are great for achieving a glossy shine on ceramic surfaces.

There are many different types of glazes suitable for gloss effects including:

• Clear glazes – Contain no colorants and result in a transparent glossy finish.
• Gloss glazes – Formulated specifically for shininess.
• Celadons – These greenish glazes can achieve lovely gloss finishes.
• Porcelains – With enough heat porcelain glazes vitrify nicely for a gloss look.

Glazes can be applied via dipping, pouring, or spraying. Multiple coats are often needed to build up an evenly glossy surface. It’s important to carefully follow the manufacturer’s instructions.

For best results, glazed pieces should be fired to the required temperature which allows the glaze to mature and become glass-like. Slow cooling in the kiln is also recommended to prevent cracking. Test tiles are useful to gauge the glossiness of different glaze recipes when fired.

Polishing

Polishing clay pieces helps give them a glossy, shiny finish. There are a couple main techniques for polishing clay:

Manual Hand Polishing

You can polish clay pieces by hand using very fine grit sandpaper, steel wool, or abrasive cloths and pads. Start with a 400+ grit sandpaper and work your way to finer and finer grits, like 600, 800, 1000. Smooth the clay surface with each grit before moving to the next finer one. Finish by rubbing the surface with 0000 steel wool in circular motions. This will make the clay smooth and shiny.

Mechanical Buffing/Polishing

For a high gloss shine, use a buffing wheel or polishing lathe. Buffing wheels are usually made of cotton or muslin material and are coated with a buffing compound. As the wheel spins at high speeds, hold the clay piece to the wheel to buff it smooth. Start with a softer buffing wheel and medium compound, then move to harder wheels and finer compounds to really make the clay shine.

Burnishing

Burnishing is a simple technique that can create a bright, glossy finish on unfired clay. It involves rubbing the surface of the clay piece with a hard, smooth tool. This compacts the clay particles and evens out the surface to a smooth, reflective shine.

The main tools used for burnishing are:
– Burnishing stones – These are hard, smooth rocks that work well for burnishing. Many types can be used like agate, hematite or marble.
– Metal burnishing tools – Items like the back of a spoon, jewelry polishing cloths or stainless steel tools are very effective.
– Wood – A smooth hardwood can be an inexpensive burnishing tool. Bamboo skewers work well.

To burnish, first ensure the clay is soft, smooth and free of cracks or tool marks. Rub the burnishing tool in a circular motion applying light pressure over the surface. Overlapping the circles to cover the entire piece. Go slowly and evenly until the desired shine is achieved. The process compacts the clay, so take care not to distort or thin delicate areas.

Mica Powders

Mica powders are finely ground minerals that can create a metallic or pearlescent sheen on clay surfaces. They come in a variety of colors like gold, silver, copper, and pearl. There are a few types of mica powders commonly used with polymer clay:

Pearl Ex – Very fine white mica powder that gives a silvery shine. It has a subtle effect compared to coarser micas.

Perfect Pearls – Available in several colors like white, bronze, and copper. The particles are slightly larger than Pearl Ex.

Interference Colors – Reveal different colors depending on the viewing angle. Popular varieties are blue/green and magenta/gold shifts.

To apply mica powders, rub a small amount directly onto the clay surface with a soft brush or fingertip. Use a light coat so the powder adheres evenly. Buff lightly with a cloth to increase shimmer after baking. Multiple thin layers of mica build up a more reflective effect than a single thick application.

Oils

Oils can create a beautiful glossy finish on polymer clay. The main types of oils used for this purpose are vegetable oils like olive oil, coconut oil, and avocado oil. Essential oils like lavender, lemon, and tea tree can also add gloss and fragrance.

To use oils, apply a thin layer over the surface of the baked clay piece. Only a small amount is needed. Rub the oil in with a soft cloth or brush, making sure to get into any crevices and textures. Let the piece sit for 10-15 minutes so the clay fully absorbs the oil. Then buff with a clean cloth to remove any excess oil and create an even shine. The finishing process works best when the clay is still slightly warm after baking. Repeated oiling and buffing will increase the glossy effect over time.

Since vegetable oils can go rancid over time, essential oils are a good option for a long-lasting gloss. Pieces made for food use should avoid oils since they can go rancid. Oils give polymer clay an elegant look, bringing out the depth and color gradations.

Wax

Wax is a great way to give clay sculptures, pottery, and other clay creations a nice glossy sheen. There are a few different types of wax that work well:

Beeswax – This natural wax made by honeybees provides a subtle gloss and protective coating. It buffs to a smooth satin finish.

Carnauba wax – Derived from the leaves of a Brazilian palm tree, carnauba wax creates a hard, shiny coating. It offers a high-gloss finish when buffed.

Paraffin wax – This mineral wax produces a medium-level gloss with a hard finish. It’s easy to buff paraffin wax to a sleek shine.

To apply wax, rub a small amount directly onto the dried clay piece using a clean, soft cloth. Let the wax fully absorb. Then use another clean, dry cloth to vigorously buff the wax coating. Buff in circular motions until you achieve the desired glossy shine.

Repeat the wax application and buffing process 2-3 times until the clay has a smooth, glossy finish. The key is applying thin layers of wax and thoroughly buffing between each layer.

Conclusion

There are several effective techniques for giving clay pieces a glossy finish. Sealers provide a protective coating that can be glossy. Resins like epoxy and polyurethane give a thick, glass-like finish when used as a top coat. Glazes flow nicely over the clay surface, leaving a shiny glazed effect after firing. Polishing with fine grit abrasives or a buffing wheel produces a smooth, glossy look. Burnishing clay by rubbing vigorously with a tool compresses the surface for added shine. Mica powders in clear mediums add glossy sparkle. Oils penetrate the clay for luster, while wax provides a protective glossy coating.

For the highest gloss finishes, casting resins tend to be the most effective, but require proper safety precautions. Glazing can also produce very glossy finishes with the right type of glaze. Sealing with a high gloss sealer or wax is the easiest option. Polishing and burnishing take effort but can bring out the natural glossiness of clay. Adding mica powder to sealers or glazes boosts the shine further.

To maintain the gloss, avoid exposing pieces to moisture, heat, or abrasives. Reapply sealers and wax periodically as needed. Handle with care to prevent scratches or dents. With proper care, many options exist to give clay art glossy, professional finishes.