Sometimes you put a glaze in the kiln and you don’t get what you think you are going to get, it depends on so many different things, time, temperature and clay type, even where you put it in the kiln. Usually i have a rough idea of what happened, but not this time.
So, i tested this Janet De Boos glaze on white and terracotta earthenware to cone 02, Frit 3134 90, Bentonite 20, Rutile flour 5, Red iron oxide 2. Being from an old book i wasn’t able to find frit 3134 anymore so substituted Frit 4124 and hoped i would still get the stable coffee/cream medium-gloss glaze.
My thinking was that because they are both borosilicate frits, then read this (Frit 3134 is similar to 3124 but without Al2O3) on digitalfire and this from Waikato Ceramics Borax Frit 4124 (Formula: Ferro 4124 (was 3124) that i would substitute frit 4124 for frit 3134, i thought i had it worked out, but nope i must have used the wrong one.
Even more confusing to me was the blue that popped up all over the other things in the kiln like these ones…maybe there was too much cobalt carbonate flying around the kiln?
I did get a fab result on my buddha head though!
I am determined to learn the answer, but for now it is a conundrum, if you have any ideas for me i would love to see your comment!
Dec 6th…did i use a clear frit instead of an opaque one? Is there such a thing? Can i opacify it now or just start again?
Dec 7th…before i change anything else, i decided i will have to be patient and just do another lot of tests “without over firing” the glaze this time…it could be that simple, you never know. As for the blue thats still a mystery for now.