Add 5% calcium carbonate to a tenmoku. What happens?

Monday 27th August 2012

In the glaze on the left (90% Ravenscrag Slip and 10% iron oxide) the iron is saturating the melt crystallizing out during cooling. GR10-K1, on the right, is the same glaze but with 5% added calcium carbonate. This addition is enough to keep most of the iron in solution through cooling, so it contributes to the super-gloss deep tenmoku effect instead of precipitating out.

Pages that reference this post in the Digitalfire Reference Database:

CaO, GR10-K1 - Ravenscrag Cone 10R Tenmoku, GR10-B Ravenscrag transparent glaze (with 10 talc), Flux, Tenmoku, Melt Fluidity, Precipitation

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