Lis Allison on fri 22 oct 10
Gadzooks!
(Like that? Great word, I've always wanted to use it....)
Anyway, I have been trying to get an exact shade of creamy yellow for an
order and did a short line blend of my base white glaze with no rutile, 6%
rutile, and 3%, 1.5%, 4.5%. All but the zero rutile gave nice yellows, but
I figured the perfect match would be about 3.5%.
So now I open the kiln and guess what, it's a nice pink.
What makes rutile go pink? Or are my eyes going? It's very unlikely I used
the wrong colourant as the rutile is clearly labelled, the wet glaze is
the brownish/yellowish of rutile, and my pink stains are all kept in the
main studio, not in the glaze mixing corner, but is that what happened?
Nothing else unusual in the kiln, white glaze, some green some brown some
maroon leaves painted on the ware. If this is a contamination problem,
what would it likely be contaminated with?
..... cue the experts......
Lis
--
Elisabeth Allison
Pine Ridge Studio
website: www.pine-ridge.ca
Pottery blog: www.studio-on-the-ridge.blogspot.com
Garden blog: www.garden-on-the-ridge.blogspot.com
James Freeman on sat 23 oct 10
Lis..
Boron in your glaze (GB, or boron frit)? Opacified with tin? Rutile
can form pinks in the presence of boron, especially where tin is also
present. I guess at 3.5% you just happened to hit the magic number!
You might try subbing zircopax for the tin (assuming I guessed right).
Good luck with your project.
...James
James Freeman
"All I say is by way of discourse, and nothing by way of advice.=3DA0 I
should not speak so boldly if it were my due to be believed."
-Michel de Montaigne
http://www.jamesfreemanstudio.com
http://www.flickr.com/photos/jamesfreemanstudio/
http://www.jamesfreemanstudio.com/resources
On Fri, Oct 22, 2010 at 5:47 PM, Lis Allison wrote:
>
> Anyway, I have been trying to get an exact shade of creamy yellow for an
> order and did a short line blend of my base white glaze with no rutile, 6=
=3D
%
> rutile, and 3%, 1.5%, 4.5%. All but the zero rutile gave nice yellows, bu=
=3D
t
> I figured the perfect match would be about 3.5%.
>
> So now I open the kiln and guess what, it's a nice pink.
>
> What makes rutile go pink?
Lis Allison on sat 23 oct 10
James and Larry,
>How about passing the base formula along so we can get a better idea?
>> .....
> Boron in your glaze (GB, or boron frit)? Opacified with tin? Rutile
> can form pinks in the presence of boron, especially where tin is also
> present. I guess at 3.5% you just happened to hit the magic number!
> You might try subbing zircopax for the tin (assuming I guessed right).
>
The glaze has Superpax in it. It's a basic white, mostly like the
"Maiolica" Glaze in Mastering Cone 6 Glazes, ie nepheline syenite, Ferro
Frit 2124, whiting, silica, EPK and Superpax. So yes, both boron and tin.
The same test a few days ago came out yellow! I have a large bucket of the
same glaze with lots of rutile that is bright yellow, too. I didn't
measure that time, just tossed in lots until it fired up a good colour.
Even if I knew what could have contaminated the pink version it would be a
big help. I'm going to mix it again and test it again just to make sure I
didn't make a mistake but if it turns pink again, how the heck will I get
the pale yellow?????? I haven't had much sucess with commercial yellow
stains, they all seem to fire out.
Sigh. This is my own fault as I was heard to say 'this will be easy, I
know how to do yellow'.
Lis
--
Elisabeth Allison
Pine Ridge Studio
website: www.pine-ridge.ca
Pottery blog: www.studio-on-the-ridge.blogspot.com
Garden blog: www.garden-on-the-ridge.blogspot.com
Larry Kruzan on sat 23 oct 10
Hey Liz - Whats wrong with PINK???? (Sorry dear)
How about passing the base formula along so we can get a better idea?
Larry Kruzan
----- Original Message -----
From: "Lis Allison"
To: Clayart@LSV.CERAMICS.ORG
Sent: Friday, October 22, 2010 4:47:46 PM
Subject: rutile line blend
Gadzooks!
(Like that? Great word, I've always wanted to use it....)
Anyway, I have been trying to get an exact shade of creamy yellow for an
order and did a short line blend of my base white glaze with no rutile, 6%
rutile, and 3%, 1.5%, 4.5%. All but the zero rutile gave nice yellows, but
I figured the perfect match would be about 3.5%.
So now I open the kiln and guess what, it's a nice pink.
What makes rutile go pink? Or are my eyes going? It's very unlikely I used
the wrong colourant as the rutile is clearly labelled, the wet glaze is
the brownish/yellowish of rutile, and my pink stains are all kept in the
main studio, not in the glaze mixing corner, but is that what happened?
Nothing else unusual in the kiln, white glaze, some green some brown some
maroon leaves painted on the ware. If this is a contamination problem,
what would it likely be contaminated with?
..... cue the experts......
Lis
--
Elisabeth Allison
Pine Ridge Studio
website: www.pine-ridge.ca
Pottery blog: www.studio-on-the-ridge.blogspot.com
Garden blog: www.garden-on-the-ridge.blogspot.com
Robert Harris on sat 23 oct 10
I've definitely had a glaze come out pinkish when I added rutile.
Unfortunately I can't remember how or why though. But you're certainly
not imagining things, and yes, you probably did add rutile.
Robert
May Luk on sat 23 oct 10
Hi Liz;
The green glaze somewhere else in the kiln might have chrome in it and
add more pink flashing then your first test firing. Try firing a whole
load of these rutile blends only and see if it's contamination (if you
can afford to)
A small percentage of rutile in glaze is supposed to be only yellow,
but it can also be pink if the Si: Al ratio changed. (
http://www.flickr.com/photos/yamerica/4155739532/in/photostream/ ) The
photo shown is a classic high calcium base glaze sans zinc for chrome
tin pinks. Since rutile is only mildly contaminated with chrome, hence
a yellow instead of pink.
Maroon stain is a form of chrome-tin pink if your painted maroon leave
is a mason stain. You can check the ingredient from their web site.
Hope this helps
May
Brooklyn
P.S, James, I think the boron is going to kill the pink. Because...
http://digitalfire.com/4sight/education/formulating_a_clear_glaze_compatibl=
e_with_chrome-tin_stains_191.html
Maybe for Liz's case, she needs to take out some whiting (CaO)
Just my 2 pence worth
On Fri, Oct 22, 2010 at 5:47 PM, Lis Allison wrote:
> Gadzooks!
>
> (Like that? Great word, I've always wanted to use it....)
>
> Anyway, I have been trying to get an exact shade of creamy yellow for an
> order and did a short line blend of my base white glaze with no rutile, 6=
%
> rutile, and 3%, 1.5%, 4.5%. All but the zero rutile gave nice yellows, bu=
t
> I figured the perfect match would be about 3.5%.
>
> So now I open the kiln and guess what, it's a nice pink.
>
> What makes rutile go pink? Or are my eyes going? It's very unlikely I use=
d
> the wrong colourant as the rutile is clearly labelled, the wet glaze is
> the brownish/yellowish of rutile, and my pink stains are all kept in the
> main studio, not in the glaze mixing corner, but is that what happened?
> Nothing else unusual in the kiln, white glaze, some green some brown some
> maroon leaves painted on the ware. If this is a contamination problem,
> what would it likely be contaminated with?
>
--
http://twitter.com/MayLuk
http://www.ceramicsbrooklyn.com/
James Freeman on sat 23 oct 10
On Sat, Oct 23, 2010 at 4:55 PM, Lis Allison wrote:
>
> Even if I knew what could have contaminated the pink version it would be =
=3D
a
> big help. I'm going to mix it again and test it again just to make sure I
> didn't make a mistake but if it turns pink again, how the heck will I get
> the pale yellow?????? I haven't had much sucess with commercial yellow
> stains, they all seem to fire out.
Lis...
How about trying red iron oxide? There is a happy little pot on my
flickr page with a cone 6 soft yellow matte that I made with either 3
or 3.5 percent RIO (can't recall which, but I'll check in the morning
when I go out to the studio). It is about three rows down on the
first page, or you can jump straight to it here:
http://www.flickr.com/photos/jamesfreemanstudio/4698361898/ . A line
blend with your base glaze going from 1% RIO up to maybe 5 or 6
percent may well get you a range of yellows to choose from.
Rutile is essentially a low grade titanium source which is
"contaminated" with iron oxide. If you try the RIO route but feel the
titanium is essential, you could simply add it in directly. I'm
guessing though that you won't need it.
Good luck!
...James
James Freeman
"All I say is by way of discourse, and nothing by way of advice.=3DA0 I
should not speak so boldly if it were my due to be believed."
-Michel de Montaigne
http://www.jamesfreemanstudio.com
http://www.flickr.com/photos/jamesfreemanstudio/
http://www.jamesfreemanstudio.com/resources
Ann Brink on sat 23 oct 10
I think you said in an earlier post that the kiln load had some green thing=
s
in it. Was there any chrome in your green glaze? Chrome and titanium are
used to get pink, and we know that rutile contains titanium. Maybe just th=
e
chrome fumes did it...
Ann Brink in Lompoc CA
>
> Even if I knew what could have contaminated the pink version it would be =
a
> big help. I'm going to mix it again and test it again just to make sure I
> didn't make a mistake but if it turns pink again, how the heck will I get
> the pale yellow?????? I haven't had much sucess with commercial yellow
> stains, they all seem to fire out.
>> --
> Elisabeth Allison
>
James Freeman on sun 24 oct 10
On Sat, Oct 23, 2010 at 11:49 PM, May Luk wrote:
I think the boron is going to kill the pink. Because...
> http://digitalfire.com/4sight/education/formulating_a_clear_glaze_compati=
=3D
ble_with_chrome-tin_stains_191.html
> Maybe for Liz's case, she needs to take out some whiting (CaO)
Hi May, Lis, all...
The chrome flashing I have seen seems to be spotty, heavier where the
chrome and the tin pot are near to one another, and less so (or
nonexistent) where they are farther away. Perhaps the cases I have
seen are aberrant or atypical. I had a lovely pot that received an
almost perfect heart-shaped pink patch on the side where it was next
to a chrome-bearing pot in the kiln. This is not to say that chrome
flashing cannot be the culprit, but Lis indicated that she employed
Superpax as her opacifier, which contains no tin (or perhaps I
misunderstood this). Also, as you point out, the boron in her glaze
would tend to argue against a chrome/tin pink developing, but would
argue for rutile pink. If, however, chrome flashing is indeed the
culprit, then the problem is simply solved by not putting
chrome-glazed pieces in that particular firing.
Though I haven't the book at hand, I seem to recall that Mimi Obstler
(sp?) discussed rutile pinks in Out of the Earth, Into the Fire. Here
is a rutile pink cone 6 glaze from my files, source unknown, probably
found in a book or on the internet somewhere. No chrome, but boron,
rutile, and tin:
Cone 6 Rutile Pink Semi-gloss
Nepheline Syenite 24
Gerstley Borate 7
Whiting 12
Lithium Carbonate 10
Magnesium Carbonate 3
Barium Carbonate 2
Silica 42
Add:
Rutile 4
Tin Oxide 3
Robin Hopper's The Ceramic Spectrum briefly mentions rutile pink,
indicating that it can occur in high calcium glazes.
Having now seen that Lis' base glaze contains no barium or strontium,
my previous suggestion to try RIO may not yield a yellow color. If
the problem is not one of chrome flashing, then tweaking the amount of
rutile and/or tin may do the trick. Mason stain muted with an
opacifier would probably work also. Third option might be to try a
base glaze with less boron. I am sure our glaze gurus will have some
even better options to offer.
...James
James Freeman
"All I say is by way of discourse, and nothing by way of advice.=3DA0 I
should not speak so boldly if it were my due to be believed."
-Michel de Montaigne
http://www.jamesfreemanstudio.com
http://www.flickr.com/photos/jamesfreemanstudio/
http://www.jamesfreemanstudio.com/resources
Lis Allison on sun 24 oct 10
On October 23, 2010, May Luk wrote:
>
> A small percentage of rutile in glaze is supposed to be only yellow,
> but it can also be pink if the Si: Al ratio changed. (
> http://www.flickr.com/photos/yamerica/4155739532/in/photostream/ ) The
>>
Yes, that is exactly the pink colour I got! Thank you. It must be the
chrome from the leaves painted on with Mason 6005. I'll re-test today
without any of that in the kiln and we'll see.
Lis
--
Elisabeth Allison
Pine Ridge Studio
website: www.pine-ridge.ca
Pottery blog: www.studio-on-the-ridge.blogspot.com
Garden blog: www.garden-on-the-ridge.blogspot.com
May Luk on wed 27 oct 10
Hi James;
I went to check the book Out of the Earth, Into the Fire and
disappointed to find no mention of the material Rutile. Off the top of
my head, I know that rutile is a 'dirty' form of Titania. in 2004,
Alisa Clauson and I tried a quick fuming test and concluded that the
rutiles that we had at the time contained trace amount of chrome.
Without a potters dictionary around, I forgot if it's classified as
opacitfier or colorant.
I have no experience of rutile in bone yellow glaze other than the
Currie Grid that I made. Based on my own (one and only and on one kind
of clay) firing. I observed that *this* yellow glaze will turn pink
when there is an increase of silica.
The explanation of the Currie Grid can be found here:
http://ian.currie.to/original/calculation_page.htm
The link, again, to the yellow glaze grid with recipe:
http://www.flickr.com/photos/yamerica/4155739532/in/photostream/
Best Regards
May
Brooklyn
On Sun, Oct 24, 2010 at 10:26 AM, James Freeman
wrote:
> Hi May, Lis, all...
>
> The chrome flashing I have seen seems to be spotty, heavier where the
> chrome and the tin pot are near to one another, and less so (or
> nonexistent) where they are farther away. =3DA0Perhaps the cases I have
> seen are aberrant or atypical. =3DA0I had a lovely pot that received an
> almost perfect heart-shaped pink patch on the side where it was next
> to a chrome-bearing pot in the kiln. =3DA0This is not to say that chrome
> flashing cannot be the culprit, but Lis indicated that she employed
> Superpax as her opacifier, which contains no tin (or perhaps I
> misunderstood this). =3DA0Also, as you point out, the boron in her glaze
> would tend to argue against a chrome/tin pink developing, but would
> argue for rutile pink. =3DA0If, however, chrome flashing is indeed the
> culprit, then the problem is simply solved by not putting
> chrome-glazed pieces in that particular firing.
>
> Though I haven't the book at hand, I seem to recall that Mimi Obstler
> (sp?) discussed rutile pinks in Out of the Earth, Into the Fire. =3DA0Her=
e
> is a rutile pink cone 6 glaze from my files, source unknown, probably
> found in a book or on the internet somewhere. =3DA0No chrome, but boron,
> rutile, and tin:
>
> Cone 6 Rutile Pink Semi-gloss
>
> Nepheline Syenite =3DA0 =3DA0 =3DA0 24
> Gerstley Borate =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA07
> Whiting =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0=
12
> Lithium Carbonate =3DA0 =3DA0 =3DA0 10
> Magnesium Carbonate =3DA03
> Barium Carbonate =3DA0 =3DA0 =3DA0 =3DA0 2
> Silica =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =
=3DA0 42
>
> Add:
> Rutile =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =
=3DA0 =3DA04
> Tin Oxide =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 3
>
>
>
>
> Robin Hopper's The Ceramic Spectrum briefly mentions rutile pink,
> indicating that it can occur in high calcium glazes.
>
> Having now seen that Lis' base glaze contains no barium or strontium,
> my previous suggestion to try RIO may not yield a yellow color. =3DA0If
> the problem is not one of chrome flashing, then tweaking the amount of
> rutile and/or tin may do the trick. =3DA0Mason stain muted with an
> opacifier would probably work also. =3DA0Third option might be to try a
> base glaze with less boron. =3DA0I am sure our glaze gurus will have some
> even better options to offer.
>
> ...James
>
--=3D20
http://twitter.com/MayLuk
http://www.ceramicsbrooklyn.com/
May Luk on wed 27 oct 10
Hi James;
The first firing was yellow tiles - in various percentages of rutile
in the same base glaze - for Liz. Then the tiles turned pink in the
next firing. Something has changed, but not the recipe, providing liz
didn't make any mistakes in mixing. What could it be? I would like to
point to other wares inside the kiln.
I was hoping to look up rutile the material itself and see what other
books have said about the material. It is very difficult to make solid
conclusion when comparing different recipes. There are just too many
variables. It seems rutile can give pinks and yellows and blues, but
under what condition? This I would love to study more when I do glaze
test again.
I did find your quote on page 183. I am still disappointed for not
seeing a section on rutile. I was looking in the index and it was not
very helpful. The shortcoming of reading printed books without the
help of a search engine.
Thanks for the glaze chat and a little brain exercise.
May
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
>
> Hi, May...
>
> I don't have that book in front of me, but according to Google Books,
> rutile is discussed on 17 different pages. =3DA0Here is a quotation from
> page 183:
>
> "Just as calcia and soda leave characteristic imprints on the color
> and surface of glazes, so too does boric oxide. =3DA0Combinations of bori=
c
> oxide materials with tin oxide (SnO2), and/or rutile (TiO2) and/or
> zinc oxide (ZnO) produce brilliant pinks."
>
> I have no doubt that your observations are correct. =3DA0My only point wa=
s
> that it was not necessary to look to outside or convoluted sources of
> the pink coloration (such as chrome fuming from traces left in the
> kiln, coming from another pot, or coming from the minute quantities
> that occasionally contaminate rutile), since the color could be
> explained by the rutile and boron alone. =3DA0Occam's Razor, and all...
>
> Take care.
>
> ...James
>
> James Freeman
>
> "All I say is by way of discourse, and nothing by way of advice.=3DA0 I
> should not speak so boldly if it were my due to be believed."
> -Michel de Montaigne
>
> http://www.jamesfreemanstudio.com
> http://www.flickr.com/photos/jamesfreemanstudio/
> http://www.jamesfreemanstudio.com/resources
>
--=3D20
http://twitter.com/MayLuk
http://www.ceramicsbrooklyn.com/
James Freeman on wed 27 oct 10
On Wed, Oct 27, 2010 at 8:01 AM, May Luk wrote:
>
> I went to check the book Out of the Earth, Into the Fire and
> disappointed to find no mention of the material Rutile.
> Based on my own (one and only and on one kind
> of clay) firing. I observed that *this* yellow glaze will turn pink
> when there is an increase of silica.
Hi, May...
I don't have that book in front of me, but according to Google Books,
rutile is discussed on 17 different pages. Here is a quotation from
page 183:
"Just as calcia and soda leave characteristic imprints on the color
and surface of glazes, so too does boric oxide. Combinations of boric
oxide materials with tin oxide (SnO2), and/or rutile (TiO2) and/or
zinc oxide (ZnO) produce brilliant pinks."
I have no doubt that your observations are correct. My only point was
that it was not necessary to look to outside or convoluted sources of
the pink coloration (such as chrome fuming from traces left in the
kiln, coming from another pot, or coming from the minute quantities
that occasionally contaminate rutile), since the color could be
explained by the rutile and boron alone. Occam's Razor, and all...
Take care.
...James
James Freeman
"All I say is by way of discourse, and nothing by way of advice.=3DA0 I
should not speak so boldly if it were my due to be believed."
-Michel de Montaigne
http://www.jamesfreemanstudio.com
http://www.flickr.com/photos/jamesfreemanstudio/
http://www.jamesfreemanstudio.com/resources
Lis Allison on thu 28 oct 10
Thank you, Clayart! You guys are great!
I've done some more tests with rutile and it looks like a mixture of 2%
rutile and .5% red iron oxide will get me very close to what my customer
wants. I'm off to hold the test tile next to her kitchen wall!
You can see the results of my tests on my pottery blog (below).
Lis
--
Elisabeth Allison
Pine Ridge Studio
website: www.pine-ridge.ca
Pottery blog: www.studio-on-the-ridge.blogspot.com
Garden blog: www.garden-on-the-ridge.blogspot.com
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