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cone 04jade/ash results

updated thu 28 dec 00


Ron Collins on wed 27 dec 00

Preliminary results of trying to get earthenware glaze from a cone 6
starting point. All trials in test kiln worked, but best lookswise is:

Cone 6 glaze:
fired to hard cone 04 in electric test kiln, fired fast, pulled when red
hot, no crazing, fired on red earthenware, all double dipped in very thick

vol.ash/pumice 63.7 smaller particles decanted in water and used, not
larger ones (threw that in the scrap clay bucket)
frit 3134 27.3
kaolin 9
bentonite 1
mixed with the decanting water to try and catch a few more minute particles
of ash
makes a nice clear at low temp, but a few impure flecks when over white
with: 5% zircopax, a nice shiny white

to this 100 g. test batch, I added
40 g. very fine jade powder
got creamy yellow, nice fat melt,

then added 2 %, not 2 g. Zinc oxide
and 2%, not 2 g. Lithium carbonate

even smoother, nicer melt
this glaze looks like cone 10 stoneware-fat smooth, not flat and
tempremental...fits better than any low fire glaze I've mixed, or bought.
don't know analysis or molecular information, just did it and it works well
would appreciate information on "stability", etc
but I'm happy regardless...

will take suggestion, and try talc for opacity instead of zircopax, as it is
Guatemalan and available here...goal is no products except what is here. Was
sent info for making 3134, but seems like a big procedure to me
Note: I was sent a suggestion of adding cullet, but this is so nice
that I don't want to do it, and don't have a need....and don't have a
source...this glaze is so nice as is
Took same basic 4 ingredient cone 6 glaze above- last night, substituted
just jade powder, no vol.ash/pumice....and got a nice fat glaze again at 04,
with a good melt-ugly green, but nice glaze...can see it would make a nice
darker with some oxides, and will work from that end too, as I have access
to a lot of it...and play with color some...but the yellow/creamy is just
nice as is, and the nice white will be useful for students- think today I'll
fire the trials in the gas kiln, trying neutral atmosphere...and drag myself
out to the sand pile to decant more ash..... it's work, but my committment
is to changing particle size, not worrying about other ingredients to add,
or other recipes, other than local substitutions for this one....AND to
reduce need for having to import anything. Wondering what effects I will
have in the luster saggar...and what it will do on my cone 5
porcelain/stoneware, reduced, but since I fire student work 06/04 in
oxidation, I'm good to go... Thanks for the input from those who know more
than myself--I DID IT !! Melinda in Guatemala