CRoeder1@aol.com on tue 23 apr 96
Hello all,
I've benefited from the recipes and advise you all have given, and I have a
successful cone 6 glaze to share. It is from (of all places) a Reader's
Digest craft book. It is a nice fat cream to beige glaze. Glossy but not
garish. Breaks to reddish brown where thin. If your clay body has much iron
in it, the reddish breaking is quite pronounced, with speckles. I use it on
white stoneware up to cone 7, and sometimes on porcelain, (though on
porcelain it is less earthy looking). It is a nice neutral earth tone.
Stores well, coats well. Well behaved and forgiving. Dark slips used
underneath will show through. BTW, it does not add up to 100.
Cream-breaking Red Cone 6
Gerstley Borate..........35
Kona F-4 Feldspar.... 15
Whiting................... 10
Barium Carb............ 5 (I substitute Strontium 3.75)
Flint ...................... 10
Tin oxide............... 13
Red Iron Oxide...... 2
I've fired it as low as 5 and as high as 7.
Candice Roeder
Under cloudy Michigan skies
Jeremy/Bonnie Hellman on wed 24 apr 96
Howdy all. I've used the Reader's Digest Crafts Book Cream Breaking Red for
years on a variety of stoneware and porcelain clays--always with great
success. I use the barium carbonate because there isn't a whole lot of it.
On white clays including porcelain, if you apply the glaze thickly, it is a
warm cream color with no red, but a hint of dark variations rather than a
bathroom tile look. The surface is quite smooth. Hard to describe but quite
attractive. Also nice on textured surfaces. Bonnie
>
>Cream-breaking Red Cone 6
>
>Gerstley Borate..........35
>Kona F-4 Feldspar.... 15
>Whiting................... 10
>Barium Carb............ 5 (I substitute Strontium 3.75)
>Flint ...................... 10
>Tin oxide............... 13
>Red Iron Oxide...... 2
>
>I've fired it as low as 5 and as high as 7.
>
>
>Candice Roeder
>Under cloudy Michigan skies
Ron Roy on wed 24 apr 96
Just a word of caution re the Cone 6 beige recipe using 5 Barium Carb.
I assume I am working with a full deck even though the recipe only totals 90.
When I calculate this glaze and compare it to all three sets of limit
formulas I use - with B2O3 in and out of unity - the answer is allways the
same - In theory this is a low fire glaze (08 at best.) At cone 6 it has
less then half the alumina and silica needed for a stable glaze at that
temperature.
Strontium is the better - by far in this case. In fact I am so sure that
significant amouts of barium will leach I will bet the cost of testing on
this one. If this glaze is to be used on ANY conceivable food bearing
surface - Substitute strontiumat 3.75 as recommended in the first post.
Wanna see a what happens to an inferior glaze in the dish washer - put a
tile with this glaze on - leave it in the dishwasher - keep one out to
compare - let us know how long it takes to start showing erosion. Doesn't
matter which version.
One of the reasons unbalanced glazes like this are so attrative is: when
there is more flux than needed for melting the silica and alumina in the
glaze, the flux starts "looking" for something to melt - that something is
the clay (mostly the silica part of clay) it is on. Most of us like that
effect (breaking on edges etc.) - which comes more naturally in hi fire
reduction. One of the reasons glaze calculation is so important for us is -
we can see this sort of thing much better using the molecular formula and
then adjust our glazes to either get more or less of the effects we want.
Ron Roy, Toronto, Canada
CRoeder1@aol.com on wed 24 apr 96
Hello.
I posted a recipe for Cream Breaking Red. I neglected to state that it is an
oxidation glaze. I have fired it in the electric kiln at cone 6 as well as
cone 7, standard Orton cones. ( I have tested it in a reduction kiln and it
comes out brown) In oxidation it is cream...breaking reddish brown (hence
the glaze name).
Sorry I omitted that bit of info.
Candice Roeder
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