This is an attempt to make Chinese-style cobalt underglazed. The underglaze should be more like watercolor, making it good for layering and gradients.
This glaze is essentially 50% metal oxides and 50% porcelain. The kaolin helps suspend the underglaze in water. The nepheline syenite and the silica form a binder and filler to help the underglaze bind and fuse to the clay body.
Since pure cobalt is an extremely saturated and powerful colorant, I add iron oxide to subdue the color.
| Material | Percent |
|---|---|
| EP Kaolin | 20 |
| Nepheline Syenite | 20 |
| Silica | 10 |
| Red Iron Oxide | 35 |
| Cobalt Oxide | 15 |
This is very much a what you see is what you get underglaze. The depth of color of the raw underglaze is very similar to the final fired appearance. The only difference is that the underglaze is red when raw and blue after firing.
| Material | Percent |
|---|---|
| EP Kaolin | 20 |
| Nepheline Syenite | 20 |
| Silica | 10 |
| Red Iron Oxide | 25 |
| Cobalt Oxide | 25 |
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