Decomposing manganese granular particles are causing this stoneware to bloat

Tuesday 9th July 2013

This is a cone 6 stoneware with 0.3% 60/insight-live.com/glossary/80">80 mesh manganese granular (Plainsman M340). Fired from cone 4 (bottom) to cone 8 (top). This body is normally stable to cone 8, but with the manganese it begins to bloat at cone 7! This is evidence that particles of manganese are generating gases as they decompose and melt at the same time as the body is vitrifying, these produce volumes and pressures sufficiently suddenly that closing channels within the maturing body are unable to vent them out.

Pages that reference this post in the Digitalfire Reference Library:

Manganese Granular, 932-Manganese compounds may begin to fume, Manganese in Clay Bodies, LOI, Bloating

This post is one of thousands found in the Digitalfire Reference Database. Most are part of a timeline maintained by Tony Hansen. You can search that timeline on the home page of digitalfire.com.