09/09/2026
Interesting glaze results! I'm working on developing some green glazes and slipped an impromptu test into the last Cone 10 reduction firing. I took my new Ochre recipe, removed the yellow ochre, and added 0.15% chrome oxide, hoping for a hint of green (chrome is a potent colorant, so a little goes a long way).
The results are in the first two images, and it's not green. Instead, I got a chrome-titanium magenta in places. The glaze has 4% rutile (titanium and iron). I already knew chrome-tin pinks and reds are a recognized glaze type, but chrome-titanium pinks and reds are new to me.
Curious whether the effect would improve in oxidation, I fired several of the new glazes in my small test kiln. This one turned green, with some opalescent blue spots. So why no magenta?
My best guess is that there's too much chrome in the glaze, enough to overwhelm titanium's ability to incorporate some of the chrome into the crystalline lattice it forms. For a chrome-tin or chrome-titanium pink, the chrome content needs to be much lower than 0.15%. But that raises the next question... why didn't the chrome turn green in reduction? My best guess there is that some of the chrome volatilized out of the glaze during the reduction firing in a way it didn't during oxidation. There's also the cooling difference... the test kiln cools much faster than the big gas kiln. Crystal formation in a glaze depends heavily on a slow cooling cycle, and the fast cooling in the test kiln likely didn't give crystals time to form.
If I ever run an oxidation firing in the big kiln, this glaze may look completely different because of the slower cooling. For now, my plan is to slowly develop a set of Cone 10 oxidation glazes to expand my color palette, and eventually find out. đŸ˜€
