Using Mason Stains
Mason Stains are stable, manufactured ceramic pigments that can be used to add consistent, reliable color to your work. Unlike raw oxides, which can change drastically during firing, Mason Stains are pre-fired and designed to hold their color across a wide range of temperatures. They’re extremely versatile and can be used in glazes, slips, underglazes, and even directly in clay.
Ways to Use Mason Stains
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Coloring Glazes – Add to a glaze base for predictable color results.
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Underglaze / Majolica Painting – Mix with a medium to create paintable colors.
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Staining Slips & Engobes – For colored surface decoration under a clear glaze.
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Coloring Clay Bodies – Wedge into porcelain or stoneware to create colored clays.
Coloring Glazes
Mason Stains can be mixed into a clear or base glaze to create reliable, vibrant colors. Typically, 5–10% stain is added to the dry weight of the glaze, though strong colors like cobalt may need less and softer hues like pinks or yellows may need more. Always pre-slurry the stain in water before adding it to avoid speckling, then mix and sieve well for an even finish. Be sure to test first — some stains interact poorly with zinc or chrome, and while most are stable across Cone 06–10, results vary depending on glaze chemistry and firing temperature.
Underglaze & Majolica Painting
Stains can also be turned into paintable colors by mixing them with water, commercial underglaze base, or brushing medium. For underglaze use, paint onto bisque, then cover with a compatible clear glaze. For majolica, paint directly over an unfired white glaze before firing. Thin, even applications work best, as heavy layers can cause crawling. Colors generally stay bright at low fire and may soften or shift at higher temperatures.
Staining Slips & Engobes
Adding Mason Stains to a white slip or engobe allows you to brush, pour, trail, or carve through colored surfaces. A common ratio is 5–10% stain to wet slip by weight, always pre-mixed with water and sieved for smoothness. Colored slips can be applied to leather hard clay for designs, sgraffito, or full coverage, then finished with a clear glaze if desired. Mishima inlay can also be done by filling carved lines with stained slip and scraping back the surface for crisp patterns.
Coloring Clay Bodies
Stains can be worked directly into clay to make colored bodies for techniques like nerikomi or agateware. This is usually done by adding 3–8% stain by weight and wedging thoroughly, or by mixing stain into slip and then reclaiming it into workable clay. Porcelain and light stoneware show colors best, while darker clays mute results. Keep additions moderate, as too much stain can reduce plasticity.
Safety
Mason Stains are stable and non-toxic when used properly, but the dry powder can be harmful if inhaled. Always wear a dust mask or N95 when handling stains in powder form, and work in a ventilated space. Clean up with a damp sponge instead of sweeping to keep dust down.
Once mixed into glaze, slip, or clay, stains are much safer to handle. For food safety, most colors are stable when properly fluxed into a glaze, but some (like certain reds, pinks, and purples) may leach. Always test on dinnerware pieces with a clear liner glaze and check manufacturer notes before using on functional ware.