Judi Buchanan on tue 22 feb 05
This is a good nickel blue from E. Cooper's glaze book that I used for =
many
years. Following it is a version where I converted it to use Strontium =
Carb
when I became a little more safety conscious. It gives the same nice =
blues
with nickel and is safer for food surfaces.
NICKEL BLUE BARIUM MATT CONE 5-6
FLINT 29%
ZINC 29%
EPK 19%
GERSTLEY BORATE 12%
BARIUM CARB. 10.9%
LITHIUM CARB. 3.9%
OPAX 10%
BENTONITE 3%
1% nickel carb- medium blue, 1% nickel +titanium dioxide- light olive, =
2%
nickel + 2% rutile - forest green.
NICKEL BLUE STRONTIUM MATT CONE 5-6
FLINT 27.1%
ZINC 27%
EPK 12.7%
GERSTLEY BORATE 10.9%
STRONTIUM CARB 7%
LITHIUM CARB 3.5%
OPAX 9.1%=20
BENTONITE 2.7
The same % of nickel gives shades of blue slightly lighter than the =
barium
glaze. The addition of 1 or 2% more lithium makes the surface slightly =
shiny
and is excellent to show scraffito.=20
Ron Roy on thu 24 feb 05
First of all recipe #1 adds to 116.8 so it is not in percentages.
Second - both glazes are highly unstable being short of both silica and alumina.
Glaze 1 should never be used as a liner glaze on any ware that could be
used to hold food because barium is toxic.
Both glazes will lose their colour under some circumstances when used with
acidic foods - and both will deteriorate in dish washers.
Using over 2% lithium carb in a glaze can result in some strange fit
problems on some clays - like shivering and crazing on the same pots.
There are some toxicity concerns with nickel.
So I would advise anyone not to use either as a liner glaze and test well
for fit problems before using on functional ware.
RR
>This is a good nickel blue from E. Cooper's glaze book that I used for many
>years. Following it is a version where I converted it to use Strontium Carb
>when I became a little more safety conscious. It gives the same nice blues
>with nickel and is safer for food surfaces.
>
>NICKEL BLUE BARIUM MATT CONE 5-6
>FLINT 29%
>ZINC 29%
>EPK 19%
>GERSTLEY BORATE 12%
>BARIUM CARB. 10.9%
>LITHIUM CARB. 3.9%
>OPAX 10%
>BENTONITE 3%
>1% nickel carb- medium blue, 1% nickel +titanium dioxide- light olive, 2%
>nickel + 2% rutile - forest green.
>
>
>NICKEL BLUE STRONTIUM MATT CONE 5-6
>FLINT 27.1%
>ZINC 27%
>EPK 12.7%
>GERSTLEY BORATE 10.9%
>STRONTIUM CARB 7%
>LITHIUM CARB 3.5%
>OPAX 9.1%
>BENTONITE 2.7
>
>The same % of nickel gives shades of blue slightly lighter than the barium
>glaze. The addition of 1 or 2% more lithium makes the surface slightly shiny
>and is excellent to show scraffito.
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
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