Lorraine Pierce on fri 14 feb 03
Hello again, I finally have my copper comparison tests out of the kiln, =
^6 oxidation, manual firing, kiln cooled quickly.
Using the Liner Clear glaze from THE book, Mastering ^6 Glazes, and =
testing a run of two different supplies of copper carbonate, I was =
amazed at the differences in color value in the fired tests. The newer =
purchase of the oxide was a VERY bright shade of medium 'spring' green, =
however I was told it would perform as my old soft grayed green had. NOT =
SO. I think it explains much of the problem I have been having in =
reproducing your glazes as pictured. It fires to a bright happy =
yellow-green. The old batch fires to a soft blue-green.=20
In a comparison of my two rutiles, light and dark, also used alone in =
the liner clear glaze, there is almost no discernable difference in the =
fired tests; Perhaps the darker rutile is SLIGHTLY grayer. I will try =
substituting titanium dioxide in the spearmint next test, and my old =
copper carbonate. No wonder you so often hear that 'glazes don't =
travel'.
As I found before, the quality and dependability of the glazes is =
perfection. Lori Pierce in New Port Richey Fl.
=20
Dan Bowen on sat 15 feb 03
regarding the copper carbonate that is brite spring green. My supplier
told me it was the same also and the lighter is no longer avalable. I found
the material I liked, and that would stay in suspension was avalable from U
S Pigment and Baileys. I am sure others also. I beleve it is a hydrate
rather than a ground form from malekite. I would like a clarification on
the hydrate processif any of the chemical guru's would care to try again.
Dan Bowen
Weirwood Station Pottery
On the Eastern Shore of Virginia
Ron Roy on mon 17 feb 03
Thanks Dan,
I don't know but I am sending this to a friend who is doing some
investigation - perhaps he will have some useful info. John has some
understanding of this as well I think.
RR
>regarding the copper carbonate that is brite spring green. My supplier
>told me it was the same also and the lighter is no longer avalable. I found
>the material I liked, and that would stay in suspension was avalable from U
>S Pigment and Baileys. I am sure others also. I beleve it is a hydrate
>rather than a ground form from malekite. I would like a clarification on
>the hydrate processif any of the chemical guru's would care to try again.
>
>Dan Bowen
>Weirwood Station Pottery
>On the Eastern Shore of Virginia
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Ron Roy on thu 20 feb 03
Hi Lori,
Thanks for posting this - I am interested to hear what your supplier says
now - and I wonder - if you would be so kind - to get MSDS for each kind -
if they have them,
Valuble infor there if we could write the mines and get a real analysis -
then you could publish the info si everyone could be aware.
I have a question - the last kind you got - was it lighter or darker - in
other words - if you changed the amount do you think you can get it to work
like the old?
RR
>Hello again, I finally have my copper comparison tests out of the kiln,
>^6 oxidation, manual firing, kiln cooled quickly.
>
>Using the Liner Clear glaze from THE book, Mastering ^6 Glazes, and
>testing a run of two different supplies of copper carbonate, I was amazed
>at the differences in color value in the fired tests. The newer purchase
>of the oxide was a VERY bright shade of medium 'spring' green, however I
>was told it would perform as my old soft grayed green had. NOT SO. I think
>it explains much of the problem I have been having in reproducing your
>glazes as pictured. It fires to a bright happy yellow-green. The old batch
>fires to a soft blue-green.
>
>In a comparison of my two rutiles, light and dark, also used alone in the
>liner clear glaze, there is almost no discernable difference in the fired
>tests; Perhaps the darker rutile is SLIGHTLY grayer. I will try
>substituting titanium dioxide in the spearmint next test, and my old
>copper carbonate. No wonder you so often hear that 'glazes don't travel'.
>
>As I found before, the quality and dependability of the glazes is
>perfection. Lori Pierce in New Port Richey Fl.
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Lorraine Pierce on fri 28 feb 03
Thanks Roy...I will try to get the info from the supplier, Highwater,
however the Clay Factory in Tampa is now closed. I am going to send out
samples to certain companies and find if they can be matched and get the
MSDS sheets.
Increasing or decreasing the amount in a glaze will not work to make the
colors more alike...one is a definite blue green the other a yellow green
when fired in the base glaze, but decreasing the amount in the Spearmint
glaze would of course, make a softer and lighter green even tho not the
value pictured. More testing . When I was in the ceramic department at the
University of North Florida this week I noticed that their copper was the
same bright shade of green as my new batch, but the person with me was no
help. More sleuthing to do. Lori Pierce in New Port Richey Fl...
----- Original Message -----
From: "Ron Roy"
To:
Sent: Thursday, February 20, 2003 12:41 AM
Subject: Re: Ron and John/ copperand rutile variations
> Hi Lori,
>
> Thanks for posting this - I am interested to hear what your supplier says
> now - and I wonder - if you would be so kind - to get MSDS for each kind -
> if they have them,
>
> Valuble infor there if we could write the mines and get a real analysis -
> then you could publish the info si everyone could be aware.
>
> I have a question - the last kind you got - was it lighter or darker - in
> other words - if you changed the amount do you think you can get it to
work
> like the old?
>
> RR
>
> >Hello again, I finally have my copper comparison tests out of the kiln,
> >^6 oxidation, manual firing, kiln cooled quickly.
> >
> >Using the Liner Clear glaze from THE book, Mastering ^6 Glazes, and
> >testing a run of two different supplies of copper carbonate, I was amazed
> >at the differences in color value in the fired tests. The newer purchase
> >of the oxide was a VERY bright shade of medium 'spring' green, however I
> >was told it would perform as my old soft grayed green had. NOT SO. I
think
> >it explains much of the problem I have been having in reproducing your
> >glazes as pictured. It fires to a bright happy yellow-green. The old
batch
> >fires to a soft blue-green.
> >
> >In a comparison of my two rutiles, light and dark, also used alone in the
> >liner clear glaze, there is almost no discernable difference in the fired
> >tests; Perhaps the darker rutile is SLIGHTLY grayer. I will try
> >substituting titanium dioxide in the spearmint next test, and my old
> >copper carbonate. No wonder you so often hear that 'glazes don't travel'.
> >
> >As I found before, the quality and dependability of the glazes is
> >perfection. Lori Pierce in New Port Richey Fl.
>
> Ron Roy
> RR#4
> 15084 Little Lake Road
> Brighton, Ontario
> Canada
> K0K 1H0
> Phone: 613-475-9544
> Fax: 613-475-3513
>
>
____________________________________________________________________________
__
> 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.
"suzhat on sun 2 mar 03
I, too, love the look of the Spearmint in THE BOOK (Mastering ^6
Glazes) but have had problems with a yellow-green product. It almost
deserves rechristening "Split Pea". I bought my copper carb at
Trinity Ceramic Supply in Dallas and will have to live with it awhile
so I'm trying alternative combinations.
I made a test tile using Trinity's White Stoneware clay and
substituting titanium dioxide for half the rutile. The result was
closer to the photo in the book where the glaze was thicker, but the
variegation of the glaze was less dramatic than that provided by the
rutile.
I've also decided that my rutile (also from Trinity) is part of the
problem because the Bone glaze from THE BOOK fires out tan. By mixing
half titanium dioxide and half rutile for the colorants, I do get a
lovely bone shade.
I've tried all the blues in the book and am quite happy with them.
Suzette Hatfield
--- In clayart@yahoogroups.com, Lorraine Pierce
wrote:
I will try
> > >substituting titanium dioxide in the spearmint next test, and my
old
> > >copper carbonate. No wonder you so often hear that 'glazes don't
travel'.
> > >
> > >As I found before, the quality and dependability of the glazes is
> > >perfection. Lori Pierce in New Port Richey Fl.
______________________________________________________________________
______
> __
> > Send postings to clayart@l...
> >
> > 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@p...
>
>
______________________________________________________________________
________
> Send postings to clayart@l...
>
> 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@p...
Lorraine Pierce on mon 3 mar 03
Suz, I was glad to hear of your Split Pea glaze...that is exactly what mine
looked like, but I am working on it and plan to succeed! It is really great
to have so many working on the pieces of the puzzle. Lori P.
----- Original Message -----
From: "suzhat "
To:
Sent: Sunday, March 02, 2003 2:26 PM
Subject: Re: Ron and John/ copperand rutile variations
> I, too, love the look of the Spearmint in THE BOOK (Mastering ^6
> Glazes) but have had problems with a yellow-green product. It almost
> deserves rechristening "Split Pea". I bought my copper carb at
> Trinity Ceramic Supply in Dallas and will have to live with it awhile
> so I'm trying alternative combinations.
>
> I made a test tile using Trinity's White Stoneware clay and
> substituting titanium dioxide for half the rutile. The result was
> closer to the photo in the book where the glaze was thicker, but the
> variegation of the glaze was less dramatic than that provided by the
> rutile.
>
> I've also decided that my rutile (also from Trinity) is part of the
> problem because the Bone glaze from THE BOOK fires out tan. By mixing
> half titanium dioxide and half rutile for the colorants, I do get a
> lovely bone shade.
>
> I've tried all the blues in the book and am quite happy with them.
>
> Suzette Hatfield
>
>
>
> --- In clayart@yahoogroups.com, Lorraine Pierce
> wrote:
> I will try
> > > >substituting titanium dioxide in the spearmint next test, and my
> old
> > > >copper carbonate. No wonder you so often hear that 'glazes don't
> travel'.
> > > >
> > > >As I found before, the quality and dependability of the glazes is
> > > >perfection. Lori Pierce in New Port Richey Fl.
> ______________________________________________________________________
> ______
> > __
> > > Send postings to clayart@l...
> > >
> > > 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@p...
> >
> >
> ______________________________________________________________________
> ________
> > Send postings to clayart@l...
> >
> > 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@p...
>
>
____________________________________________________________________________
__
> 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.
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