| Monthly Tech-Tip | Feb 14-15, 2026 - Major Server Upgrade Done | No tracking! No ads! |
In this case, lithium carbonate was added to the G1214Z1 cone 6 matte glaze base. These formed sometime later.

This picture has its own page with more detail, click here to see it.
These crystals were found in a months-old bucket (about 2 gallons). These can appear even quicker, depending on factors like temperature, electrolytes in your water or solubility in the materials (evens frits can be slightly soluble). The glaze slurry should be screened periodically (or immediately if you note the particles when glazing a piece). This is an 80 mesh sieve. Note the brush, using one of these gets the glaze through the screen much quicker than using a rubber spatula. The loss of material on the screen is tiny and inconsequential to the glaze. But it is crucial because these particles do not melt at cone 6, they will certainly mar the fired glaze surface if undetected.
| Glossary |
Precipitation
Crystals or crystalline particles will often form over time in ceramic glaze slurries that contain slightly soluble materials. |
Buy me a coffee and we can talk