Step 1 of a speckled dolomite matte at cone 6 oxidation: This result is good enough to prove it is doable

Saturday 18th April 2015

I am looking to match the insight-live.com/glossary/125">reduction-fired dolomite matte mug on the right, but in cone 6 oxidation. I must duplicate the glaze color and surface character. But more difficult is the speckle size, color, density and edge bleeding. The speckle is the biggest challenge, but I met that by making my own by mixing the body and G2926B glossy glaze 50:50 and adding 10% black stain. Then I slurry it, dry it, fire it in a crucible (which I make from L4404A with an L3693E liner), crush it by hand using my shusher and screen it. I am using G2934 cone 6 magnesia matte as the glaze on this mug on the left. I add 0.5% minus 20 mesh speck to achieve this result. The next step in this project is to sieve out the smallest specks, switch to the G2934 matte glaze in the speckle recipe (the specks are too shiny here), and switch to dark brown stain instead of black. I will also need to control the degree to which the specks bleed at their edges (by adjusting the glaze:body ratio) and tune the degree of matteness (by adjusting cooling speed of the kiln). A small amount of green or blue stain is also needed to match the glaze color. There is no question that an authentic reproduction is possible; methodical testing with good records is the key to accomplishing that.

Pages that reference this post in the Digitalfire Reference Library:

Making your own crucibles to make your own speckle, Reduction speckle: A product of iron particles in the body And the atmosphere of the firing, Blue stain in a low-fire porcelain: Creates the blue-white color of reduction-fired bodies, Making my own home-made fired speckle for cone 6, Reduction Speckle, Magnesia Matte

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.