Cobalt sulfate is a cobalt-derived compound used to create intense blue tones in ceramics. Although less common than cobalt oxide, it is used to obtain decorative effects in glazes and engobes.
Due to its solubility in water, it allows for better control of the intensity of the blue color in creations. This makes it an ideal choice for overglaze decoration techniques where precision and tonal variation are sought.
In addition, unlike cobalt oxide, cobalt sulfate can produce a less dense and lighter blue, with a delicate appearance, which gives it versatility in decorative works and allows the creation of transparency effects in glazes.
Interesting Fact
Its use dates back thousands of years: cobalt-based pigments have been found in ceramic objects from ancient Egypt and Persia. This precious mineral has also been a key ingredient in China's famous blue and white porcelain since the Tang Dynasty (618-907 AD), underscoring its historical and cultural relevance in the ceramic arts over the centuries.
Helpful Tip
Be sure to dilute the cobalt sulfate correctly, as it is extremely potent, and always color test small samples to avoid an excessively dark shade.
