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^6 electric copper red? reply to paul t.

updated thu 23 may 02

 

Craig Clark on tue 21 may 02


Sam, about fifteen years ago we tried to make a cone six copper red
oxidation glaze while I was in school. We had mixed results but did end up
with a copper reddish glaze.
We did infact use a local reduceing agent, I don't remember the
percentage, but it was silicon carbide (I distinctly remember making the
trip to the ceramics store over in Houston to get the stuff.)
If I remember correctly, the stuff silicon carbide did not stay in
suspension very well and the glaze tended to be splotchy.
Craig Dunn Clark
619 East 11 1/2 st
Houston, Texas 77008
(713)861-2083
mudman@hal-pc.org

----- Original Message -----
From: "Jeff Tsai"
To:
Sent: Wednesday, May 22, 2002 2:57 PM
Subject: Re: ^6 electric copper red? Reply to Paul T.


> Sam Wrote:
>
> "Copper red in ^6 electric? Not that I've heard of yet...."
>
> It's not impossible, but it isn't easy as far as I've heard. I think what
a
> cone 6 oxidation copper red needs as an important ingredient is a
> self-reducing agent in the glaze, like fine silican carbide. It will cause
> enough local reduction to the copper to produce the red, but I'm sure it's
a
> tricky and probably splotchy thing.
>
> -jeff
>
>
____________________________________________________________________________
__
> Send postings to clayart@lsv.ceramics.org
>
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Jeff Tsai on wed 22 may 02


Sam Wrote:

"Copper red in ^6 electric? Not that I've heard of yet...."

It's not impossible, but it isn't easy as far as I've heard. I think what a
cone 6 oxidation copper red needs as an important ingredient is a
self-reducing agent in the glaze, like fine silican carbide. It will cause
enough local reduction to the copper to produce the red, but I'm sure it's a
tricky and probably splotchy thing.

-jeff

Tommy Humphries on wed 22 may 02


Craig, you went to the wrong store for your silicon carbide...the grades I
have seen in ceramic shops would be in the 200-300 grit sizes...you need to
hit the lapidary shops and get some 1000 grit silicon carbide used in rock
tumblers as a pre polish before switching over to cerium oxide (tin oxide
works too!) 1000 grit silicon carbide will go into a glaze just as easily
as 200 mesh silica, and I bet it would disperse better for a more even
copper red.

Tommy


----- Original Message -----
From: "Craig Clark"
To:
Sent: Tuesday, May 21, 2002 11:40 AM
Subject: Re: ^6 electric copper red? Reply to Paul T.


> Sam, about fifteen years ago we tried to make a cone six copper red
> oxidation glaze while I was in school. We had mixed results but did end up
> with a copper reddish glaze.
> We did infact use a local reduceing agent, I don't remember the
> percentage, but it was silicon carbide (I distinctly remember making the
> trip to the ceramics store over in Houston to get the stuff.)
> If I remember correctly, the stuff silicon carbide did not stay in
> suspension very well and the glaze tended to be splotchy.
> Craig Dunn Clark
> 619 East 11 1/2 st
> Houston, Texas 77008
> (713)861-2083
> mudman@hal-pc.org
>
> ----- Original Message -----
> From: "Jeff Tsai"
> To:
> Sent: Wednesday, May 22, 2002 2:57 PM
> Subject: Re: ^6 electric copper red? Reply to Paul T.
>
>
> > Sam Wrote:
> >
> > "Copper red in ^6 electric? Not that I've heard of yet...."
> >
> > It's not impossible, but it isn't easy as far as I've heard. I think
what
> a
> > cone 6 oxidation copper red needs as an important ingredient is a
> > self-reducing agent in the glaze, like fine silican carbide. It will
cause
> > enough local reduction to the copper to produce the red, but I'm sure
it's
> a
> > tricky and probably splotchy thing.
> >
> > -jeff
> >
> >
>
____________________________________________________________________________
> __
> > Send postings to clayart@lsv.ceramics.org
> >
> > You may look at the archives for the list or change your subscription
> > settings from http://www.ceramics.org/clayart/
> >
> > Moderator of the list is Mel Jacobson who may be reached at
> melpots@pclink.com.
>
>
____________________________________________________________________________
__
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
>