One well known artist blends these the two types, permanent and washable, with a powdered ceramic pigment, in the proportions appropriate to get as much hardness as possible but not so much that it is difficult to clean up the screen. The powder should not be a pure ceramic stain, it should bee mixed with a melter medium so it fires to an adequate degree and similar thermal expansion as the body.

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The logo on the left was rubber-stamped using an ink mix made of Mason 6666 black stain in a glycerine carrier. During firing, the glaze is shedding off. The stain is refractory yet still bleeding excessively into the overlying glaze. Further, it does not melt during firing, so it does not glass-bond with the body below. And, it either develops only a fragile interface with the glaze above, or sheds it off.
The piece on the right mixes the stain 50:50 with a glossy transparent glaze; from that it stamps better, inherits better lay down, accepts the overglaze better, and dries harder.

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The blue is melting and bleeding profusely into the glaze. The green is the opposite - refractory, stiffening the glaze enough to trap bubbles and sit on the surface as a dry, unmelted layer. Under the glaze, these problems would be magnified (the blue bleeding more, the green causing crawling and blistering).
Stains are not ceramic; they are ceramic additives. Stains are not considered safe for direct food contact. Stains are expensive. Stains don't suspend in water, paint poorly and dry as a loose powder.
Both of these (and others) need to be added, as a minor percentage, to a ceramic carrier (one with CMC gum and a mix of ceramic materials tailored to melt to the desired degree and have a compatible chemistry to develop the color (as per manufacturer guidelines).

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These black stain-water mixes were painted onto bisque and an overglaze was applied. Out the kiln, this crawling happened. Why? Many stains are refractory, thus do not glass-bond with the body. And they repel being wetted by the molten glaze on top. Stains need to be mixed with a stain medium that both supplies a bonding glass (for firing) and a clay to suspend the slurry and dry-harden and dry-bond it. One medium option used to be Gerstley Borate, it was both plastic (so it dried like a clay and suspended the slurry), and it was a melter. It was just a matter of tuning the percentage to optimize performance. One problem was that the best mix of those ended up using 70% stain (whereas 15-20% is theoretically enough). A better option is to use a full-fledged medium, a recipe. Each of the ingredients is there for a purpose. This provides the ultimate flexibility to tune the mix properties for brushing and firing (also enabling minimizing the percentage of stain).
| Glossary |
Silk screen printing
Silk screen printing is one of the best options for hobbyists and potters to reproduce crisp and detailed decoration. But there are many details to know. |
| Glossary |
Stain Medium
A stain medium (or ceramic medium) is a mix of powdered ceramic materials that impart ceramic properties that stain powders lack in themselves (e.g. ability to form a hard ceramic that fits the underlying body or overlying glaze. |
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