Can frits be partially soluble? Yes, and here is what that means.

Wednesday 5th February 2014

These 1 mm-sized crystals were found precipitated in a couple of gallons of glaze containing 85% Ferro insight-live.com/material/356">Frit 3195. They are cubical, hard and insoluble. Why and how to do they form? Many frits are slightly soluble, the degree to which they are is related to the length of time the glaze is in storage, the temperature, the electrolytes and solubles in the water, interactions with other material particles present and the diligence of the manufacturer in mixing, correctly achieving the target chemistry and firing. The solutes interact or saturate to form insoluble species that crystallize and precipitate out as you see here. These crystals can be a wide range of shapes and sizes and come from leaded and unleaded frits. In industry this issue is not generally a problem because glazes are used soon after being made.

Pages that reference this post in the Digitalfire Reference Library:

Ferro Frit 3195, A glaze slurry precipitates flakes, G2926B glaze can precipitate crystals like this, Precipitated crystals from a glaze having 60% lead bisilicate frit, Ooids in Glazes, Precipitation, Frit

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