| Monthly Tech-Tip | No tracking! No ads! | 
The cone 03 porcelain cup on the left has 10% Cerdec encapsulated stain 239416 in the G2931K clear base. The surface is orange-peeled because the glass is full of micro-bubbles that developed during the firing. Notice that the insides of the cups are crystal-clear, no bubbles. So here they are a direct product of the presence of the stain. The glaze on the right has even more stain, 15%. But it also has a 3% addition of Zircopax (zircon). Suppliers of encapsulated stains recommend a zircon addition, but are often unclear about why. Here is the reason: It is a "fining agent".
| Materials | Zircopax Zirconium silicate, its principle use in ceramics is as an opacifier in glazes. It is an expensive material, but less so than tin oxide. | 
| Materials | Zircon | 
| Troubles | Orange Peel Surface Orange peel is a defect or physical property of ceramic glazes | 
| Glossary | Glaze Bubbles Suspended micro-bubbles in ceramic glazes affect their transparency and depth. Sometimes they add to to aesthetics. Often not. What causes them and what to do to remove them. | 
| Glossary | Fining Agent Individual tiny bubbles in a glaze melt can coalesce around the undissolved particles of a fining agent, the growing bubble swallowing others around it and finally exiting at the surface. | 
| Glossary | Encapsulated Stain This is a type of stain manufacture that enables the use of metal oxides (like cadmium) under temperature conditions in which they would normally fail. | 
| Glossary | Ceramic Stain Ceramic stains are manufactured powders. They are used as an alternative to employing metal oxide powders and have many advantages. | 
Buy me a coffee and we can talk