Why not find a friendly

Stephen Richard

Why not find a friendly ceramics person who will let you fire something you have already done in their kiln.  Then you can lcompare results.   I think the marking mentioned is more likely to be devitrification due to slow cooling, than residues from the glazes, which have a lot of glass as well as metals in them.

Stephen Richard

blogs at: http://www.verrier-glass.blogspot.com/ and  http://www.glasstips.blogspot.com/

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