lucien m koonce on sun 21 jan 01
Has anyone experience with inclusion stains? These are colors obtained with
cadmium and selenium pigments encapsulated in a zircon sphere. I am
interested in knowing the percentage added into a white engobe. While
testing will determine the exact color saturation that I am looking for, I
need a starting point. Thanks, in advance.
~Lucien Koonce
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Click on http://lmkoonce.home.mindspring.com and visit my on-line gallery.
L M Koonce / Robbins, NC, USA
David Hendley on mon 22 jan 01
It takes quite a bit of stain to adequately color an engobe.
8-10% would be a good starting point for average saturation
at stoneware firing temperatures.
--
David Hendley
Maydelle, Texas
hendley@tyler.net
http://www.farmpots.com/
----- Original Message -----
From: lucien m koonce
To:
Sent: Sunday, January 21, 2001 5:39 PM
Subject: inclusion stains
| Has anyone experience with inclusion stains? These are colors obtained
with
| cadmium and selenium pigments encapsulated in a zircon sphere. I am
| interested in knowing the percentage added into a white engobe. While
| testing will determine the exact color saturation that I am looking for, I
| need a starting point. Thanks, in advance.
|
| ~Lucien Koonce
..
Wade Blocker on mon 22 jan 01
Lucien,
5 % is a good starting point. Mia in ABQ
Paul Lewing on mon 22 jan 01
It takes about 2-3 % to make a noticeable color, 5-7% to make a strong
color, and about 8-10% to make a saturated color in a glaze. More than
that is wasted, because you don't really get any stronger color. To
make the same intensity of color in a slip takes much more colorant-
maybe 25-30% for agood strong color. And I doubt if you could ever get
a really saturated color in a slip.
Paul Lewing, Seattle
Gavin Stairs on tue 23 jan 01
At 06:39 PM 1/21/01, Lucien Koonce wrote:
>Has anyone experience with inclusion stains? These are colors obtained with
>cadmium and selenium pigments encapsulated in a zircon sphere.
Dear Lucien,
I can't help you with your inquiry, but I thought I'd pass on a note
regarding your description of the inclusion stain structure. I don't
believe they are truly encapsulated in a zirconia sphere, as you
imply. They are apparently simply a zirconia frit, with included colorant
oxides. The zirconia structure is difficult to melt with common fluxes at
our customary temperatures, so the effect is of "encapsulation", even
though no true capsule exists.
There has been at least one discussion of these stains on the list, and you
should be able to find it in the archive. If memory serves, there was the
usual caution to test, test, test, if inclusion stains are used bearing
lead, cadmium or any of the other potential toxins, as complete containment
is not guaranteed under all circumstances, and final responsibility for
safety rest with you, the potter, rather than with the stain manufacturer.
Gavin
Gavin Stairs
Stairs Small Systems
921 College St., # 1-A
Toronto, Ontario, Canada M6H 1A1
phone: (416)530-0419 stairs@stairs.on.ca
Ceramic Design Group on tue 23 jan 01
on 1/22/01 1:23 PM, Paul Lewing at pjlewing@WORLDNET.ATT.NET wrote:
> It takes about 2-3 % to make a noticeable color, 5-7% to make a strong
> color, and about 8-10% to make a saturated color in a glaze. More than
> that is wasted, because you don't really get any stronger color. To
> make the same intensity of color in a slip takes much more colorant-
> maybe 25-30% for agood strong color. And I doubt if you could ever get
> a really saturated color in a slip.
> Paul Lewing, Seattle
>
I would concur with Paul.
We have used inclusion pigments in temperature ranges of cone 06-10, in both
glazes and engobes, in oxidizing as well as reducing atmospheres. We have
used pigments from Ceredec and Mason.
For example, in our cone 4-5 oxidation clear, we ran tests starting at 1%
all the way to 15%, and our best colors were in the 7-9% range. Also, with
the addition of a small amount of opacifier, these colors certainly
brightened up considerably.
Another trick, so to speak, is to take a base glaze and add a commercial
underglaze to it. For example, take a volume of your glaze, and then add a
volume of liquid underglaze. We have used Amaco Velvets as well as Amaco
LUG's for this and the range of produceable colors is quite broad.
Best
Jonathan
Michelle Lowe on tue 23 jan 01
At 08:23 PM 1/22/2001 +0000, Paul Lewing wrote:
> To
>make the same intensity of color in a slip takes much more colorant-
>maybe 25-30% for agood strong color. And I doubt if you could ever get
>a really saturated color in a slip.
We have used the inclusion stains in slip and gotten some pretty nice color
response. I'm not sure it is technically "saturated", but I sure like the
way it comes out, even at cone 10 reduction.
Just my experience.
Mishy
Michelle Lowe, potter in the Phoenix desert \|/ |
mishlowe@amug.org -O- | |
mishy@desertdragonpottery.com /|\ | | |
|_|_|
http://www.desertdragonpottery.com ____ |
http://www.amug.org/~mishlowe -\ /-----|-----
( )
<__>
John Hesselberth on tue 23 jan 01
Gavin Stairs wrote:
>At 06:39 PM 1/21/01, Lucien Koonce wrote:
>>Has anyone experience with inclusion stains? These are colors obtained with
>>cadmium and selenium pigments encapsulated in a zircon sphere.
>
>Dear Lucien,
>
>I can't help you with your inquiry, but I thought I'd pass on a note
>regarding your description of the inclusion stain structure. I don't
>believe they are truly encapsulated in a zirconia sphere, as you
>imply. They are apparently simply a zirconia frit, with included colorant
>oxides. The zirconia structure is difficult to melt with common fluxes at
>our customary temperatures, so the effect is of "encapsulation", even
>though no true capsule exists.
Hi Lucien and Gavin,
I did find out a little more about these since the last discussion on
them. I tracked down one of the key patents (US 5,389,402) which degussa
holds. It gives a little of the history of inclusion stains and says
the "casing" (their word) is oxidic or silicate and can contain ZrO2,
SnO2, Al2O3, and ZrSiO4; although those based on zirconium silicate and
tin dioxide are preferred. It also the references the original
invention/patents (US 3,847,639 and 4,874,433). Full text of these is
now available on the U.S. Patent and Trademark web site if you're
interested in some pretty esoteric reading.
Regards, John
"The life so short, the craft so long to learn." Hippocrates, 5th cent.
B.C.
Gene Arnold on mon 7 feb 05
I was just flipping through some pottery catalogs and saw inclusion =
stains and didn't really know what they were.
Do you use them to make a stain for use in texture or do you make a =
glaze as one would do with mason stains???
So what are inclusion stains and how would you use them.=20
Just curious.
Gene & Latonna
mudduck@mudduckpottery.com
www.mudduckpottery.com
Mayssan Shora Farra on tue 8 feb 05
Hello Gene:
Inclusion stains are like Mason stains ( some of them are Mason stains).
the only difference is that they are encapsulated so the reds, yellows and
oranges stay bright at high tempratures.
They claim to stay bright to ^10, but since I only fire to ^6 I can only
say that they absolutely stay true to color to ^6.
I hope this answers your wonderings:)
Mayssan
http://www.clayvillepottery.com
David Hendley on tue 18 dec 07
----- Original Message ----- >
> I just recently starting coloring clay with stains. Are ALL Mason
> stains are inclusion stains, or does this just refer to the process
> of "encapuslating" selenium and cadmium?
The latter - "inclusion stains" refers only to stains that use zirconium
to encapsulate otherwise unhealthy and dangerous glaze ingredients.
David Hendley
Maydelle, Texas
david(at)farmpots(dot)com
http://www.farmpots.com
Paul Lewing on tue 18 dec 07
On Dec 18, 2007, at 1:02 PM, Sarah Dolin wrote:
I just recently starting coloring clay with stains. Are ALL Mason
stains are inclusion stains, or does this just refer to the process
of "encapuslating" selenium and cadmium?
Only the cadmium ones are inclusion stains. No other oxide (actually
the coloring crystal in there is not an oxide, which is what makes it
so unstable) requires it. By the way, don't assume that that makes
the cadmium unavailable, biologically speaking. We don't know if
there's unencapsulated cadmium floating around in there or not, and
it's nasty stuff. If you judge by the leaching standards, it's six
times as toxic as lead. I suspect that there's some unencapsulated
cadmium in there, because you can get a little whiff of sulphur when
you open a bag of it. Part of the coloring crystal is a sulphate.
Paul Lewing
www.paullewingtile.com
Sarah Dolin on tue 18 dec 07
Good afternoon!
I'm new to the list and hoping that someone can help me out with an
important question about Mason stains.
I just recently starting coloring clay with stains. Are ALL Mason
stains are inclusion stains, or does this just refer to the process
of "encapuslating" selenium and cadmium? I was unable to contact
Mason directly via their website. The info that I found in the
clayart archives seems to confirm that it's only for cadmium and
selenium.
Thanks in advance for your help. I've learned so much from the
reading archives and am looking forward to participating.
Sarah Dolin
Vince Pitelka on tue 18 dec 07
Sarah Dolin wrote:
> I just recently starting coloring clay with stains. Are ALL Mason
> stains are inclusion stains, or does this just refer to the process
> of "encapuslating" selenium and cadmium? I was unable to contact
> Mason directly via their website. The info that I found in the
> clayart archives seems to confirm that it's only for cadmium and
> selenium.
Sarah -
Welcome to Clayart. I use a lot of Mason stains in my colored clay work.=
=20
You can see it at the website link below if you wish. As I understand it=
,
the term "inclusion stains" specifically refers to stains where toxic or
unstable coloring oxides are melted into a zircon glass in stable
laboratory conditions, rendering them relatively chemically inert at the
temperatures we fire studio ceramics. It becomes especially critical wit=
h
highly toxic materials like cadmium, and the invention of inclusion stain=
s
reintroduced some of the colors available with materials like cadmium tha=
t
had pretty much been banned from utilitarian clay.
All commercially-prepared ceramic stains are fritted materials, meaning
that they have been combined with glass-forming materials and melted to a
glass, cooled, and re-ground to a powder. We call such a prepared
material a "frit." The whole idea is to eliminate problems of contact
toxicity, water solubility, or in-glaze stability. Most stains are just
an ordinary silica glass matrix that in dry powdered form have the
advantages of being stable, non-toxic (except for the inhalation hazard -
always wear a dust mask when handling stains), and insoluble in water, bu=
t
will fuse completely into the glaze melt at glaze-firing temperatures.=20
Inclusion stains are only those stains specifically made as a zircon glas=
s
where the ground stain particles remain as chemically inert inclusions
suspended in the glaze melt, even at high-fire temperatures, thus the
cadmium or other toxic material is only minimally released into the glaze
melt. Remember that even though the fritted stain has been re-ground to =
a
powder, the individual stain particles are of enormous proportions as
compared to the molecules in the glaze melt, and thus a relatively small
amount of the potentially toxic material is accessible to the glaze melt.=
=20
You get the color but drastically reduce the danger.
Hope that helps to clarify things -
- Vince
--=20
Vince Pitelka
Appalachian Center for Craft
Tennessee Technological University
vpitelka@dtccom.net
http://iweb.tntech.edu/wpitelka/
Ivor and Olive Lewis on thu 20 dec 07
Dear Paul Lewing ,
Would you please check your source of information about Cadmium =
Compounds.
I suspect you mean Cadmium Sulphide, not Cadmium Sulphate.
The former is insoluble in Water but soluble in acid. The latter is very =
soluble in Water.
Wishing you a very Happy Festive Season.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Paul Lewing on thu 20 dec 07
On Dec 19, 2007, at 10:08 PM, Ivor and Olive Lewis wrote:
I suspect you mean Cadmium Sulphide, not Cadmium Sulphate.
I did indeed mean sulphide, not sulphate. Oops.
Paul Lewing
www.paullewingtile.com
Ivor and Olive Lewis on fri 21 dec 07
Thought that might be the case Paul.
I would be loath to use anything containing Cadmium. Years ago I was =
warned not to even pick up an article that has been electroplated with =
Cadmium.
Knowing that these stains are safe for handling during processing does =
nothing to assure me that the stuff cannot become destabilised during =
firing even if the encapsulating material is difficult to dissolve in a =
vitreous melt. The Phase Diagrams for CdO-B2O3 suggests a lot of =
reactivity below 1000 deg C, but I can find nothing for Cadmium Borate =
in the C.R.C handbook
Best regards,
Ivor
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