The Allure of Oxides in Ceramics: A Journey Through Time and Colour

As a ceramicist, one of the most fascinating chapters in the story of my craft is the use of oxides. These vibrant or subtle mineral compounds are responsible for some of the most iconic ceramic glazes we see today, and their story stretches back thousands of years.

Oxides, in essence, are compounds that contain oxygen and a metal element. In ceramics, they play a starring role in coloring and transforming glazes during firing. From the deep blues of cobalt oxide to the earthy greens of copper, these pigments are at once mysterious and elemental.

The roots of oxide use in ceramics are ancient. Archaeologists and historians have traced the first uses of iron oxide back to the earliest glazed pottery of Mesopotamia and Egypt. Iron oxide, rich in iron (Fe2O3), was prized for its warm browns and reds, often seen in the terracotta that still inspires us today. In fact, the Terracotta Army of China—dating back to the Qin dynasty—bears witness to how iron oxide and other minerals created bold, lasting colors.

But it wasn’t just iron. Copper oxide, for instance, has a rich history as well. Its use is perhaps most famously tied to the blue-green glazes of ancient China. When copper oxide is added to a glaze, firing can transform it into a stunning turquoise, a color so prized that it became known as “Jade.” Over time, copper oxide also traveled westward, influencing Islamic ceramics and later European pottery, where deep turquoise became a symbol of wealth and refinement.

Cobalt oxide, too, is a titan in this story. Its roots stretch back to ancient Persia, where cobalt was used to create vivid blue glazes on tilework. Later, in the 18th century, the Dutch masters took cobalt oxide to Europe, where it became a hallmark of Delftware—those blue-and-white ceramics that still evoke nostalgia and elegance.

Today, we still lean on these ancient roots. Iron, copper, cobalt, and other metal oxides are not just materials; they are storytellers. They connect us to potters of the past, who experimented with what the earth gave them. And every time we fire a piece, we’re continuing that dialogue—using knowledge that spans millennia to create something uniquely ours.

Of course, these oxides aren’t just about color—they’re about chemistry. When we mix oxides into a glaze, we’re harnessing a balance of temperature, chemistry, and timing. Each kiln firing is a leap of faith, where we trust that those subtle mineral compounds will reveal themselves as rich, layered surfaces. And when they do—when that iron oxide reveals its deep rust, or that copper oxide blooms into turquoise—there’s a moment of magic.

So, the next time you see a cobalt-blue plate, or a deep iron-speckled bowl, take a moment to honor those oxides. They are not just color—they are a bridge to the past, and a spark for the future.

How does that feel for the depth and vibe you were aiming for?