Reduction glaze gone astray returns to color in an oxidation refire

Wednesday 6th December 2017

Refired to 1950F. The recipe is very insight-live.com/glossary/42">flux-heavy (high feldspar) dolomite:spodumene matte, zero silica, 4% tin oxide and less than 1% iron oxide. Sounds like crystallization territory. The plate on the left is the way it normally fired. On the right the way it started firing. The mug on the bottom looked like the plate on the right, but look what happened after refiring at 1950F in oxidation! The tin is likely a catalyst for the crystallization that occurred in the original result. Could be a fragile mechanism. This underscores the need for a period of oxidation at the end of a normal reduction firing.

Pages that reference this post in the Digitalfire Reference Library:

Bamboo Glaze, Reduction Firing, Refiring Ceramics, Glaze is Off-Color

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