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copper carbonate in slip decoration

updated wed 30 apr 97

 

The Allens on wed 9 apr 97

-------------------
I've been using a great formula obtained from this list for slip which does
beautifully for all colors except green. I've been adding plain copper carb=
for
the green and it doesn't behave well at all after the glaze firing. =
(bubbles
and flakes). Does anyone know if mason stains will do better? Thanks for =
your
help and patience.....if it weren't for this group I would be completely =
lost.

Carla Allen
ridgerun=40scrtc.blue.net

Sue Hintz on thu 10 apr 97

I use 10% Copper Carb in 100 g of ball clay and get a beautiful green---easy to
When it is bisqued it turns brown but when fired to cone 6 it is lovely.

I'd like to know what slip recipe you are using. I haven't been able to get a p
mason stain in mine.

Colette R. Palamar on thu 10 apr 97

Carla,

Have you tried a very low percentage of chrome? I've had pretty good luck
making green slip with chrome. Im not sure how it will work in your
formula, but its probably worth a try. Try 2-3 percent at first, and then
add more or less if the color isn't quite right. Good luck!

Colette

Colette Palamar
palamar@bgnet.bgsu.edu

Larry Phillips on mon 14 apr 97

In article <01IHHZ1PN3KY934ZAF@cluster.unca.edu>,
Sue Hintz writes:
> ----------------------------Original message----------------------------
> I use 10% Copper Carb in 100 g of ball clay and get a beautiful green---easy t
> When it is bisqued it turns brown but when fired to cone 6 it is lovely.
>
> I'd like to know what slip recipe you are using. I haven't been able to get a
> mason stain in mine.

Here's a little recipe I have had good luck with. I can't claim credit
for it, as it came from Leon at GreenBarn in Surrey (Langley?) BC.

Ball Clay 1300g
Silica 400g
Custer Feldspar 300g

I mix this with enough water to make about 4 quarts, and divide it
into 4 equal parts, and add different colourants to each one, making
4 different colours....

White No colourants (very nice, bright white)

Blue Cobalt Carbonate 20-50g, giving light to dark blue

Green Copper carbonate 50-80g, giving light to dark green.

Black Manganese Dioxide 50g
Redi Iron Oxide 50g
Cobalt Carbonate 10g

Leon says these work well from cone 06 to cone 10. I have tried them
at cone 6, and they are very nice.

After bisquing, the green shows as a muddy pinkish-brown, the blue
as a sort of a chalky pastel blue, and the black as dark reddish-brown,
but with a transparent overglaze at cone 6, they really brighten up
and turn the proper colours.

"Rafael Molina-Rodriguez (Rafael Molina-Rodriguez)" on tue 22 apr 97

Carla :

I've tried on numerous occasions and have never had luck with copper
carb in a slip. No matter the percentage, it always looks like too much.
The appearance, after firing, is as though there is so much metallic oxide
that it is too refractory and does not want to melt. And, I thought chrome
and rutile were the only ones that behaved this way.

My solution for a green slip is a combination of cobalt carbonate and
chrome oxide. Try .5 % cobalt carb and 2 % chrome oxide. If this is not
to your liking try 1 % cobalt carb and 3 % chrome oxide. It yields a nice
deep green.

Good luck!

Rafael
rmr3431@dcccd.edu
>>> The Allens 04/09/97 07:49am >>>
----------------------------Original message----------------------------
-------------------
I've been using a great formula obtained from this list for slip which does
beautifully for all colors except green. I've been adding plain copper carb
for
the green and it doesn't behave well at all after the glaze firing. (bubbles
and flakes). Does anyone know if mason stains will do better? Thanks
for your
help and patience.....if it weren't for this group I would be completely lost.

Carla Allen
ridgerun@scrtc.blue.net