For thousands of years, artists have created colorful designs and patterns on pottery using a variety of natural pigments. The origins of painting pottery can be traced back to ancient times, when early humans first discovered that certain colored clays and minerals could be used to decorate utilitarian vessels and objects. Over time, pottery decoration became more sophisticated, with artisans mastering techniques like slips, engraving, terra sigillata, and glazing to produce ornate ceramics.
Early Pigments Used on Pottery
Some of the earliest pigments used for coloring pottery include:
- Iron oxides – Red and yellow ochres provided by iron oxides were among the most common early pottery pigments. Red ochre adds a bright red-orange color while yellow ochre provides a golden yellow hue.
- Manganese dioxide – This mineral yields a black pigment when ground into a fine powder. Ancient potters used manganese pigments to create black-figure pottery designs.
- Copper minerals – Malachite (green), azurite (blue), and copper carbonates produce green and blue colors. These pigments were used by ancient Egyptian faience artists.
- Clays – Natural clays occur in various colored varieties like white, red, brown, yellow, and gray. Pigments were produced by selectively grinding certain colored clays.
- Carbon – Soot and charcoal produced by burning organic materials provided an early black pigment.
- Calcium carbonate – This white mineral found in limestone, seashells, and eggshells was used as a white pigment.
In addition to these naturally occurring minerals and ores, some early pottery pigments were made by roasting or heating certain metal ores. For example, ancient Egyptian cobalt blue pigment was synthesized by heating copper and quartz crystals with potassium carbonate to isolate the cobalt element and produce a vibrant blue vitreous material.
Slips and Engobes
One of the most prevalent methods of decorating pottery was using slips and engobes. A slip is a fluid suspension of clay body and other minerals that can be used to coat the surface of leather-hard pottery objects. Engobes are similar to slips, but contain larger particles and more fluxing materials like quartz, giving them a thicker consistency.
To create colored slips and engobes, natural pigments would be added and mixed into the clay suspension. Some common colors included:
- White – Calcium carbonate, limestone, kaolin clay
- Red – Iron oxides, ochre
- Black – Manganese dioxide, carbon
- Yellow – Iron oxides
- Green – Copper carbonates, glauconite
- Blue – Copper carbonate, cobalt aluminate
- Brown – Iron oxides, manganese dioxide
The pigmented slip or engobe could then be used to freely paint designs, patterns, and figures onto the surface of pottery objects. When fired, the slip bonds with the clay body to produce a permanent colored coating. The technique of using slips originated in ancient Mesopotamia and Egypt around 3000 BC and allowed artisans to add decorative color and opacity to ceramics.
Sgraffito
Related to slips, sgraffito is a decorative technique that involves scratching away part of a surface slip coating to reveal the different colored clay underneath. First, a white or light-colored slip is applied over the leather-hard clay object. Once dry, a dark-colored slip is then brushed on top. Using a knife or sharp tool, the artisan scrapes and carves patterns through the layers to expose the lighter base coat. This reveals a striking two-tone design in the finished pottery after firing.
The sgraffito technique dates back to at least the 7th century BC in North Africa and the Middle East. It gained popularity in Europe during the Middle Ages and Renaissance periods as well.
Terra Sigillata
Meaning “sealed earth” in Latin, terra sigillata was a type of watery clay slip first developed by Greek potters and later refined by the Romans. It consisted of a refined white clay suspension with added pigments that produced a smooth, glossy surface coating. When fired, the terra sigillata coating would fuse to the clay body to form a glossy surface that retained its color.
Red was the most common terra sigillata color produced by iron oxide pigments. But additions like manganese dioxide created black sigillata, while cobalt and copper compounds produced blue and green variants. The fine surface allowed decorative burnishing and polishing as well. Terra sigillata was regularly used in ancient Roman pottery from the 1st century BC to 3rd century AD and later revived in the 19th century.
Glazes
While slips bond to the clay surface, glazes form a glassy coating that is fused to the body by firing the pottery at high temperatures. The development of glazes was a significant breakthrough in pottery decoration. Glazes are made by mixing silica, flux, and stabilizer compounds with powdered pigments to create suspensions that vitrify in the kiln into transparent or opaque glass-like layers. Here are some of the pigments used to create colored glazes:
| Pigment | Source | Color |
|---|---|---|
| Cobalt oxide | Cobalt aluminate | Blue |
| Copper carbonate | Malachite, azurite | Blue, green |
| Antimony yellow | Naples yellow | Yellow |
| Manganese dioxide | Pyrolusite | Black |
| Tin oxide | Cassiterite | White, opacifier |
| Iron oxide | Red ochre | Red, brown |
Glazing first emerged in the Middle East around 1500 BC and came to dominate Chinese porcelain and Near East pottery by 700 AD. Later European, Persian, Arab, and Turkish potters perfected colored glaze recipes as both an aesthetic and functional pottery coating.
Underglaze Paints and Stamps
Underglaze decoration involves applying pigmented paints on the clay surface that get covered by a transparent glaze coating during firing. Underglaze painted designs fuse into the glaze layer. Cobalt blue underglaze was prevalent in Chinese porcelain from the 14th century Ming dynasty. In Europe, underglaze painting on tin-glazed pottery arose in Renaissance Italy to decorate maiolica ware.
Stamping is another underglaze technique where pigmented clay slurry is applied through stencils onto the leather-hard surface before glazing and firing. This allows repetitive motifs and patterns to quickly decorate pottery. Stamped ancient Greek black-figure and Roman red-figure pottery used iron oxide clay slips stamped with wood/clay stamps.
Overglaze Decorations
Overglaze techniques add decorative colors on top of an already mature glazed and fired ceramic. These include:
- Enamels – Pigments are ground into a gum or glass binder, painted on, and fired again at low temperatures to fuse the enamel layer.
- Gilding – Gold and silver leaf or powder is applied over the glaze then fired to produce a lustrous gilded decoration.
- Lusterware – Pottery is reheated in a kiln containing metal oxides like copper and silver to produce an iridescent metallic sheen.
Chinese potters first developed overglaze painting in the 6th century Tang dynasty while Near East lusterware thrived in 9th century Iraq and Egypt. Later European maiolica, Delftware, and faience all employed overglaze techniques.
Conclusion
From prehistoric times up to the modern era, pottery artists across the globe have invented ingenious methods to color and adorn ceramics using locally available materials. The earliest pottery pigments were comprised of clays, carbonates, and metal oxides ground into powdered suspensions and applied as slips, engobes, or paints. Glazing technology revolutionized pottery decoration by allowing pigments to fuse into glassy coatings. Over centuries of discovery, potters produced increasingly advanced recipes for coloring pottery that became essential to styles like ancient Greek red-figure pottery, Chinese porcelain, Turkish Iznik ware, Dutch Delftware and more.
While many ancient pottery pigments were derived from nature, the 20th century saw a shift towards synthetic pigments like cadmium and cobalt aluminate. Today, ceramic artists still apply traditional techniques like slips, underglazes, and overglazes but have an immense array of prepared colored pigments available allowing for boundless creativity in pottery decoration.