Jeanean Slamen on sat 7 dec 96
"Shaner Oribe" for C10-11R, contributed by earlier this year by stalwart Clayart
Eitel, gave beautiful results on several pieces I fired in early November:
Custer Spar 30.58
Flint 25.05
Whiting 22.13
Talc 7.72
EPK 12.42
Bone Ash 1.04
Bentonite 1.04
Copper Carb 5.20
Formula & Analysis (courtesy of Insight)
CaO .68 14.87%
MgO .18 2.85
K2O .10 3.59
Na2O .04 1.05
Fe2O3 .00 .20 (Where was this from --- the bentonite?)
Al2O3 .29 11.53
SiO2 2.78 65.29
RATIO 9.62
EXPAN 6.91
I mixed an 800 gram batch and sprayed it with my Critter onto a lidded casserole
shallow serving dish with applied decoration on the rim, two juicers and a small
bowl.
It was well behaved, staying put, not crazing and gracefully compensating for my
admittedly novice spraying skills (I STILL can't reliably judge when the thickne
right)and is/was a BEAUTIFUL glaze for serving ware: a medium-deep transparent g
green which was a medium, soft blue where it pooled slightly in the bottom of th
bowl and bottom of the juicers. Everyone who saw it wanted it... I didn't sell
pieces, though, because I wanted to live with it for awhile to see how it
handled everyday life.
On Thanksgiving, as I was washing up the shallow serving dish (which had been us
serve relatively firm squares of Southern cornbread dressing as well as some oys
dressing) and the juicer (lemon juice), I noticed there were lighter, bleached l
spots scattered on the bottom of the serving dish and a ring of affected surface
bottom of the juicer.
Doesn't this mean the glaze is too soft? The Al-Si ratio looked right, but when
comparing the formula to the typical limit formula for C10 glazes, I notice that
though all the other components compare favorably to the limits, both the alumin
silica are just below the published lower limits for these elements.
What would be the best strategy for adjusting (hardening) the formula? Just add
Al and Si, keeping the ratio as close as possible to the current level?
I'm also interested in the fact that the serving dish was affected by brief cont
only moderately moist food... Before anyone makes rude assertions about my dress
assure you they were delicious --- not vile, acidic, gloppy fare! :>))) I can't
which side of the dish had which dressing, but one side was affected more than t
other. I think the only potentially reactive ingredients in either dressing wer
giblets, oysters, and maybe pecans.
Can anyone offer advice? Have I mis-diagnosed it as a hardness issue? I want t
on this so I can salvage a really promising glaze.
Jeanean Slamen
Missouri City (Houston), Texas
Part-time functional potter
High fired (nat. gas) reduction stoneware and porcelain
Ron Roy on sun 8 dec 96
>----------------------------Original message----------------------------
>"Shaner Oribe" for C10-11R, contributed by earlier this year by stalwart
>Clayart
>Eitel, gave beautiful results on several pieces I fired in early November:
>Custer Spar 30.58
>Flint 25.05
>Whiting 22.13
>Talc 7.72
>EPK 12.42
>Bone Ash 1.04
>Bentonite 1.04
>
>Copper Carb 5.20
>On Thanksgiving, as I was washing up the shallow serving dish (which had
>been us
>serve relatively firm squares of Southern cornbread dressing as well as
>some oys
>dressing) and the juicer (lemon juice), I noticed there were lighter,
>bleached l
>spots scattered on the bottom of the serving dish and a ring of affected
>surface
>bottom of the juicer.
>
>Doesn't this mean the glaze is too soft? The Al-Si ratio looked right,
>but when
>comparing the formula to the typical limit formula for C10 glazes, I
>notice that
>though all the other components compare favorably to the limits, both the
>alumin
>silica are just below the published lower limits for these elements.
>
>What would be the best strategy for adjusting (hardening) the formula?
>Just add
>Al and Si, keeping the ratio as close as possible to the current level?
>Jeanean Slamen.
Hi Jeanean,
I'm so hungry after reading your post.
Well I concure - the glaze is short of Alumina and Silica for cone 10-11.
The copper may be a part of the problem as well. It has a reputation of
making glazes more soluble.
I did a revision raising the alumina and the silica to the "right" levels
keeping the ratio at least similar. That lowered the expansion a bit more
than I thought prudent so I then raised the KNaO at the expence of some
MgO.
I for one would appreciate you trying the result and testing with some of
that wonderful sounding food. Could I have some in "98?"
Custer 34.0
Silica 29.0
Whiting 19.0
Talc 5.0
EPK 12.0
Bone ash 1.0
Bentonite 1.0
Ratio 9.85
Expansion is down a bit but it will not be a problem.
We are all working with slightly different analysis so don't let that throw
you off - Please let me know if you have questions - I'll sing for a
dinner.
Ron Roy
Toronto, Canada
Evenings, call 416 439 2621
Fax, 416 438 7849
LizzardOL@aol.com on wed 11 dec 96
Re: the thread on Oribe bleaching. Yeah - could you post the recipe for the
turky stuffing as well?
>"Shaner Oribe" for C10-11R, contributed by earlier this year by stalwart
>Clayart
>Eitel, gave beautiful results on several pieces I fired in early November:
>Custer Spar 30.58
>Flint 25.05
>Whiting 22.13
>Talc 7.72
>EPK 12.42
>Bone Ash 1.04
>Bentonite 1.04
>
>Copper Carb 5.20
>On Thanksgiving, as I was washing up the shallow serving dish (which had
>been us
>serve relatively firm squares of Southern cornbread dressing as well as
>some oys
>dressing) and the juicer (lemon juice), I noticed there were lighter,
>bleached l
>spots scattered on the bottom of the serving dish and a ring of affected
>surface
>bottom of the juicer.
>
>Doesn't this mean the glaze is too soft? The Al-Si ratio looked right,
>but when
>comparing the formula to the typical limit formula for C10 glazes, I
>notice that
>though all the other components compare favorably to the limits, both the
>alumin
>silica are just below the published lower limits for these elements.
>
>What would be the best strategy for adjusting (hardening) the formula?
>Just add
>Al and Si, keeping the ratio as close as possible to the current level?
>Jeanean Slamen.
Hi Jeanean,
I'm so hungry after reading your post.
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