Decoration has always been the most engaging part of creating with clay for me. I consider it right from the beginning of a piece, when my energy is high and my creative spark is fresh, rather than leaving it until the end. I have a penchant for bright, attention-grabbing, punchy tones that spark a strong emotional response—joy, energy, even perhaps a little bit of chaos. Bright colors make my work visually interesting and dynamic, and they make it feel alive and full of movement.
A Sense of Endless Possibilities
Initially, to create my pieces, when studio time was limited, I utilized a mono-printing technique; however, as my time allocated to studio activities grew, so too did my desire to develop my creative process. Newsprint was replaced by plaster bats. By decorating a piece in this way, the imagery could become an integral part of the form itself, embedded within the walls of the piece, rather than simply applied after bisque to the surface like paint on a canvas. Working on plaster allowed for impulsiveness and surprises, which was exciting to me.
Creating monotypes with plaster is a spontaneous and versatile process—drawing with slip trailers and painting with colored slip: painting directly onto the plaster; using underglazes like watercolors; using more bold, thick, and opaque mark making, like with acrylics; screen printing onto the plaster slab with underglazes; or even combining all these processes to create unique, mixed-media work. There is so much room to experiment and that sense of endless possibility really invigorates me.
Preparing a Bat and Colored Slips
For this technique, first cast a plaster bat on which to decorate. I cast slabs onto a flat, smooth surface and use cottle boards to contain the plaster, ensuring that the surface onto which I am pouring the plaster is as smooth and even as possible for the best quality work. I check that my table or desk is level in all directions using a level, so that when I pour the plaster, the bat is level too. When making bats and slabs, I always use #1 Pottery Plaster, which is finer and more durable than other types of plaster. After the plaster is set, allow the bat to fully dry, so that it can absorb the moisture from the slip and turn it to a leather-hard slab for handbuilding (1).
The next stage is to prepare colored slips. I work exclusively with Scarva’s porcelain FLAX Paper Clay. It is best to use a decorating slip that matches the clay body so that the shrinkage rates are the same. In this instance, that is not possible as the small particles of flax paper would clog up my fine-tipped slip trailers, but to keep the shrinkage consistent, I use a porcelain decorating slip, which I then color with Mason stains. Using between 4% and 8% stain per weight of slip will achieve the bright, bold colors I like to work with (2). Once the slip and stain have been mixed together, pass the mixture through a 120-mesh sieve, then add premixed sodium silicate (1 tsp) and water (150 ml) solution to the colored slip, a drop at a time, until the slip reaches the consistency of milk (3). The addition of the water/deflocculant mixture makes the slip much more fluid, but without oversaturating it and dulling the quality of the color. It also means that the slip will move through the thin-tipped slip trailers with ease and without clogging, allowing me to make fast, fluid, expressive marks on the plaster. Decant some of the colored slips from the tubs into slip trailers to prepare for drawing directly onto the plaster. The remaining decorating slip is stored in lidded tubs for later use.
Decorating the Surface
Now it’s time to get to work on the plaster. The most complex part of the process is remembering to work in reverse. When you paint directly onto canvas, you work from background to foreground; however, for this process, you must begin with the foreground. So you will start with the slip trailers, adding a range of impulsive marks and patterns (4), working your way across the bat, trying to find balance in the composition. The dry plaster quickly wicks away moisture from the slip-trailed marks allowing you to move on to the next layer, usually drops of color squeezed from the slip trailers (5).
Sometimes I work instinctively with squiggles, circles, and crosses, then other times I am more controlled and create patterns using various colors (6). Moving onto the paintbrushes allows me to flood the background (7). You are trying to achieve balance in the composition as you work across the plaster, building up the background with a range of brightly colored slips until all the plaster surface is covered (8, 9). As you progress, the plaster continues to draw moisture from the decorating slips.
Casting a Clay Transfer Slab
I roll long coils of a contrasting clay and use them to build walls around the perimeter of the plaster bat, ensuring that they are pressed down firmly and will not allow the wet clay to seep underneath (10). The FLAX Paper Clay casting slip is poured onto the decorated plaster bat to create an even layer (around ¼ inch (6 mm) in depth) covering the entire colored surface (11). It is then left to firm up. The plaster gets to work again, drawing the moisture from the wet casting slip. After waiting about an hour, cut away the clay walls surrounding the edge. This is an important step as it allows the clay to shrink further as it dries and prevents tears in the decorated surface. After 3 to 5 hours, the clay slip has firmed to a leather-hard state, and can then be gently lifted up from the plaster surface using a soft rib to reveal the image underneath (12).
Creating a Base
While the clay slab firms up slightly (it should be able to stand upright on its edge, but remain flexible enough to bend into a cylinder shape), roll out a 5-mm-thick slab for the base of the vessel. I do this in the same clay body as the casting slip. When the decorated slab of clay is ready to be removed entirely from the plaster bat, set it on a canvas sheet and use a right-angle ruler to cut it into a rectangle to make the base level (13).
Next, shape the decorated slab around a cardboard tube (14). Score and slip the edges pressing them firmly against each other and against the cardboard tube, then secure the join by rolling over it with a pony roller (15). Once the joins are tidied up, you can remove the tube and shape the vessel into an oval. Allow both the bottomless vessel and the base slab to firm up to the same moisture level.
From the slab trimmings, cut out small shapes (16) to apply to the vessel’s exterior to add further interest (17). When the vessel walls and base are firm enough, score, slip, and join them; however, don’t trim the shape of the base until the two are secured together and the joins tidied (18).
Drying
The vessels are dried slowly, covered at first with a plastic bag for a week, and then uncovered for another two weeks before they are bisque fired to 1832°F (1000°C) in an electric kiln. Preferring to keep the tactile quality of the colored porcelain on the outside of the vessel, I glaze only the inside, using three coats of Mayco Stroke & Coat in a color that complements the external walls and glaze fire to 2264°F (1240°C). At this temperature, the colored porcelain slips become much more vibrant, and to further enhance their vibrancy and protect the walls from stains, coat the work using two coats of HG Tile Protector.
Donna Bloye is a ceramic artist from Belfast, Northern Ireland. Some will know her from her Instagram page, Oto NI pottery (@oto.ni.pottery), where she regularly shares reels of her processes and images of her screen-printed ceramics. Others will know her as the winner of the Great Pottery Throwdown in 2024. She has a passion for ceramic surface decoration and is currently developing a body of work that combines traditional screen-printing processes with flax paper porcelain vessels. Learn more at www.otonipottery.com.
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Decoration has always been the most engaging part of creating with clay for me. I consider it right from the beginning of a piece, when my energy is high and my creative spark is fresh, rather than leaving it until the end. I have a penchant for bright, attention-grabbing, punchy tones that spark a strong emotional response—joy, energy, even perhaps a little bit of chaos. Bright colors make my work visually interesting and dynamic, and they make it feel alive and full of movement.
A Sense of Endless Possibilities
Initially, to create my pieces, when studio time was limited, I utilized a mono-printing technique; however, as my time allocated to studio activities grew, so too did my desire to develop my creative process. Newsprint was replaced by plaster bats. By decorating a piece in this way, the imagery could become an integral part of the form itself, embedded within the walls of the piece, rather than simply applied after bisque to the surface like paint on a canvas. Working on plaster allowed for impulsiveness and surprises, which was exciting to me.
Creating monotypes with plaster is a spontaneous and versatile process—drawing with slip trailers and painting with colored slip: painting directly onto the plaster; using underglazes like watercolors; using more bold, thick, and opaque mark making, like with acrylics; screen printing onto the plaster slab with underglazes; or even combining all these processes to create unique, mixed-media work. There is so much room to experiment and that sense of endless possibility really invigorates me.
Preparing a Bat and Colored Slips
For this technique, first cast a plaster bat on which to decorate. I cast slabs onto a flat, smooth surface and use cottle boards to contain the plaster, ensuring that the surface onto which I am pouring the plaster is as smooth and even as possible for the best quality work. I check that my table or desk is level in all directions using a level, so that when I pour the plaster, the bat is level too. When making bats and slabs, I always use #1 Pottery Plaster, which is finer and more durable than other types of plaster. After the plaster is set, allow the bat to fully dry, so that it can absorb the moisture from the slip and turn it to a leather-hard slab for handbuilding (1).
The next stage is to prepare colored slips. I work exclusively with Scarva’s porcelain FLAX Paper Clay. It is best to use a decorating slip that matches the clay body so that the shrinkage rates are the same. In this instance, that is not possible as the small particles of flax paper would clog up my fine-tipped slip trailers, but to keep the shrinkage consistent, I use a porcelain decorating slip, which I then color with Mason stains. Using between 4% and 8% stain per weight of slip will achieve the bright, bold colors I like to work with (2). Once the slip and stain have been mixed together, pass the mixture through a 120-mesh sieve, then add premixed sodium silicate (1 tsp) and water (150 ml) solution to the colored slip, a drop at a time, until the slip reaches the consistency of milk (3). The addition of the water/deflocculant mixture makes the slip much more fluid, but without oversaturating it and dulling the quality of the color. It also means that the slip will move through the thin-tipped slip trailers with ease and without clogging, allowing me to make fast, fluid, expressive marks on the plaster. Decant some of the colored slips from the tubs into slip trailers to prepare for drawing directly onto the plaster. The remaining decorating slip is stored in lidded tubs for later use.
Decorating the Surface
Now it’s time to get to work on the plaster. The most complex part of the process is remembering to work in reverse. When you paint directly onto canvas, you work from background to foreground; however, for this process, you must begin with the foreground. So you will start with the slip trailers, adding a range of impulsive marks and patterns (4), working your way across the bat, trying to find balance in the composition. The dry plaster quickly wicks away moisture from the slip-trailed marks allowing you to move on to the next layer, usually drops of color squeezed from the slip trailers (5).
Sometimes I work instinctively with squiggles, circles, and crosses, then other times I am more controlled and create patterns using various colors (6). Moving onto the paintbrushes allows me to flood the background (7). You are trying to achieve balance in the composition as you work across the plaster, building up the background with a range of brightly colored slips until all the plaster surface is covered (8, 9). As you progress, the plaster continues to draw moisture from the decorating slips.
Casting a Clay Transfer Slab
I roll long coils of a contrasting clay and use them to build walls around the perimeter of the plaster bat, ensuring that they are pressed down firmly and will not allow the wet clay to seep underneath (10). The FLAX Paper Clay casting slip is poured onto the decorated plaster bat to create an even layer (around ¼ inch (6 mm) in depth) covering the entire colored surface (11). It is then left to firm up. The plaster gets to work again, drawing the moisture from the wet casting slip. After waiting about an hour, cut away the clay walls surrounding the edge. This is an important step as it allows the clay to shrink further as it dries and prevents tears in the decorated surface. After 3 to 5 hours, the clay slip has firmed to a leather-hard state, and can then be gently lifted up from the plaster surface using a soft rib to reveal the image underneath (12).
Creating a Base
While the clay slab firms up slightly (it should be able to stand upright on its edge, but remain flexible enough to bend into a cylinder shape), roll out a 5-mm-thick slab for the base of the vessel. I do this in the same clay body as the casting slip. When the decorated slab of clay is ready to be removed entirely from the plaster bat, set it on a canvas sheet and use a right-angle ruler to cut it into a rectangle to make the base level (13).
Next, shape the decorated slab around a cardboard tube (14). Score and slip the edges pressing them firmly against each other and against the cardboard tube, then secure the join by rolling over it with a pony roller (15). Once the joins are tidied up, you can remove the tube and shape the vessel into an oval. Allow both the bottomless vessel and the base slab to firm up to the same moisture level.
From the slab trimmings, cut out small shapes (16) to apply to the vessel’s exterior to add further interest (17). When the vessel walls and base are firm enough, score, slip, and join them; however, don’t trim the shape of the base until the two are secured together and the joins tidied (18).
Drying
The vessels are dried slowly, covered at first with a plastic bag for a week, and then uncovered for another two weeks before they are bisque fired to 1832°F (1000°C) in an electric kiln. Preferring to keep the tactile quality of the colored porcelain on the outside of the vessel, I glaze only the inside, using three coats of Mayco Stroke & Coat in a color that complements the external walls and glaze fire to 2264°F (1240°C). At this temperature, the colored porcelain slips become much more vibrant, and to further enhance their vibrancy and protect the walls from stains, coat the work using two coats of HG Tile Protector.
Donna Bloye is a ceramic artist from Belfast, Northern Ireland. Some will know her from her Instagram page, Oto NI pottery (@oto.ni.pottery), where she regularly shares reels of her processes and images of her screen-printed ceramics. Others will know her as the winner of the Great Pottery Throwdown in 2024. She has a passion for ceramic surface decoration and is currently developing a body of work that combines traditional screen-printing processes with flax paper porcelain vessels. Learn more at www.otonipottery.com.
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