What is cobalt oxide colour used for? What is difference between cobalt oxide and cobalt carbonate? How do you use oxides in ceramics?
Cobalt oxide (Co3O4) is a consistent, reliable oxide and a common colorant in pottery. It is available in powdered form and is blackish in color. It is a very strong oxide and using very small quantities yields bright, intense blues. In ceramics, cobalt oxide is used mainly in slips, washes, and glazes and can be applied through brushwork, decals, or other surface decorating techniques. It can also be added to porcelain or stoneware clay. Because cobalt oxide is not as finely powdered as cobalt carbonate, cobalt oxide is more likely to create blue specks, a quality that we believe can be quite beautiful!
All pigments for ceramics are intermixable so why not get creative and experiment by mixing your own completely fresh color. During the firing process, the colors fuse extra vigorously creating purity, intensity, and brilliance. The colors are stronger, therefore, significantly less percentage is needed to create vivid colors making them excessively cost-effective.
How to use Cobalt Oxide Colour in the pottery?
Because of the strength of this oxide as a colorant, glazes containing cobalt can produce halos and flashing during firings. Suggested concentrations for preparation of slips and glazes are as follows:
In slips: 0.25 - 2%
In glazes: 0.25 - 1%
When mixed with magnesium in the proper concentrations, cobalt oxide can produce purples and lavenders. When properly combined with titanium, greens can result. Additional colors and effects can be achieved using cobalt oxide, and we recommend that you consider consulting some of the many wonderful glaze books available.
When using ceramic pigments in glazes, usually in concentrations of 1–10%, a little more care must be taken because some pigment systems react with materials in a glaze.
Assay: 99.5% trace metals basis
Surface Area: BET 40-70 m²/g (typical range)
Density: 6.11 g/mL at 25°C (lit.)
Formula Weight: 240.80 g/mol
COBALT OXIDE - Cobalt (II,III) Oxide Ceramics Pigments and Stains
- Brand: BASF
- Product Code: Oxide - Cobalt Oxide - Co3O4
- SKU: Co3O4
- Availability: 96