Two bases, 2% copper additions. Which is the better transparent?

Tuesday 28th July 2015

Wrong. It is the one on the right. While the copper looks so much better in that fluid one on the left, that melt mobility comes at a cost: insight-live.com/trouble/3">blisters. As a clear glaze it is no glossier than the other one, but it runs into thicker zones at the bottom and they blister. This is because the high mobility coupled with the surface tension blows bubbles as gases of decomposition travel through (in a normal cooling kiln they break low enough that mobility is insufficient to heal them). The fired glass in the one on the left is also not as hard, it will be more leachable, it will also craze more easily and be more susceptible to boron-blue devritrification. But as a green? Yes it is better.

Pages that reference this post in the Digitalfire Reference Library:

G3806C - Cone 6 Clear Fluid-Melt transparent glaze, Comparing the melt fluidity of four copper blue cone 6 glazes, Transparent Glazes, Melt Fluidity, Leaching, Base Glaze

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.