MS NANCY PARKER on fri 18 oct 96
I would like to know if anyone has a recipe for a cone 10 black clay.
Thanks,
Charlie Parker
Stern HQ on sat 19 oct 96
Charlie, I have used very dark brown clay, one available from Mile Hi
Ceramics here in Denver is "Chestnut", and added black mason stain to
it. It comes out almost black.
On Fri, 18 Oct 1996, MS NANCY PARKER wrote:
> ----------------------------Original message----------------------------
> I would like to know if anyone has a recipe for a cone 10 black clay.
>
> Thanks,
> Charlie Parker
>
Bob Hanlin on sat 19 oct 96
Charlie:
I have used a clay from Aardvark Clay in Santa Rosa called Cassius Basaltic.
It is quit plastic and fires to a true black at ^4-5 and black with warts
thereafter in oxidation. It worked in my kiln with a small orton cone 5.
It's a bugger to work with if you use any other clays near it. Picks up
little white flecks that are a real bummer to pick out with the needle tool.
Got the info on this from a Virginia Cartwright workshop it attended some
years ago.
>----------------------------Original message----------------------------
>Charlie, I have used very dark brown clay, one available from Mile Hi
>Ceramics here in Denver is "Chestnut", and added black mason stain to
>it. It comes out almost black.
>
>On Fri, 18 Oct 1996, MS NANCY PARKER wrote:
>
>> ----------------------------Original message----------------------------
>> I would like to know if anyone has a recipe for a cone 10 black clay.
>>
>> Thanks,
>> Charlie Parker
>>
>
>
Bob Hanlin
3504 N. Tulsa
Oklahoma City, OK 73112
e-mail bhanlin@ionet.net
John Guerin on sat 19 oct 96
I use the Cassius Basaltic clay also. But since I am firing at a lower
temperature, I add manganese dioxide powder to it to get a true black.
Samantha Tomich on sun 20 oct 96
I read in a catalog that when you use this clay you should use gloves to
protect you from the manganese dioxide seeping into your pores. Someone
else told me that you can coat your hands with vegetable oil before
throwing...? What safety measures, if any, do you folks use when
handling these types of clay?
Sam in Hawaii
Darrol F. Shillingburg on sun 20 oct 96
Charlie;
I use a cone 6 clay called B3Brown distributed by Laguna Clay. It fires dark
brown in oxidation and black in reduction. When "reduction cooled" from cone 4,
it goes matte black. It is very plastic when wet, but seems a little fragile in
the hard leather hard stage. I suspect this is caused by the additional iron and
manganese oxides in the clay. It may give you a simular effect to adding mason
stains to a dark clay body. Nevertheless, it is the most true "black" of the
clays I have worked with.
Darrol in Elephant Butte NM
>----------------------------Original message----------------------------
>Charlie:
>I have used a clay from Aardvark Clay in Santa Rosa called Cassius Basaltic.
>It is quit plastic and fires to a true black at ^4-5 and black with warts
>thereafter in oxidation. It worked in my kiln with a small orton cone 5.
>It's a bugger to work with if you use any other clays near it. Picks up>
>little white flecks that are a real bummer to pick out with the needle tool.
>Got the info on this from a Virginia Cartwright workshop it attended some
>years ago.
>Charlie, I have used very dark brown clay, one available from Mile Hi
>Ceramics here in Denver is "Chestnut", and added black mason stain to
>it. It comes out almost black.
>
>On Fri, 18 Oct 1996, MS NANCY PARKER wrote:
>
>> ----------------------------Original message----------------------------
>> I would like to know if anyone has a recipe for a cone 10 black clay.
>>
>> Thanks,
>> Charlie Parker
>>
Darrol F. Shillingburg on mon 21 oct 96
Hi Sam,
Good point. I only handbuild and work fairly dry at that. I have, however, not
gotten an MSDS on the B3Brown clay. For sure Laguna would supply that. There are
no cautions mentioned in the Ceramic King catalogue (my supplier). The question
is whether or not the maganese dioxide is fritted. If so, it should be safe to
handle, if not? If there are any cautions on the MSDS I will post them on this
list.
Thanks for the question.
Darrol in Elephant Butte NM
----------------------------Original message----------------------------
I read in a catalog that when you use this clay you should use gloves to
protect you from the manganese dioxide seeping into your pores. Someone
else told me that you can coat your hands with vegetable oil before
throwing...? What safety measures, if any, do you folks use when
handling these types of clay?
Sam in Hawaii
Ron Roy on sat 2 nov 96
There was a brief flurry of discussion about black clay and the use of
Manganese Dioxide as a colourant a while ago - just a reminder to be aware
of the health hazards associated with Manganese.
Ron Roy
Toronto, Canada
Evenings, call 416 439 2621
Fax, 416 438 7849
John Guerin on mon 4 nov 96
What are the health hazards associated with manganese dioxide?
Frances Evans on fri 23 may 97
Dear Clayarters:
After a 10 year hiatus whilst renting studio space and using a cone 6
porcelain body, I am now back at art school for a summer course on garden
containers.
The instructor wants us to work with black clay and I am wondering if any
clayarters have experience working with this body. If so, I'd love to share
ideas.
Frances Evans
Toronto, Canada
Frances_Evans@goodmedia.com
ret on sat 24 may 97
On Fri, 23 May 1997, Frances Evans wrote:
>.... I am now back at art school for a summer course on garden
> containers.
>
> The instructor wants us to work with black clay and I am wondering if any
> clayarters have experience working with this body. If so, I'd love to share
> ideas.
Frances, before you use black clay, find out from your instructor exactly
WHAT makes the clay black. The clay supplier will have that
information. I'm sure it contains a fairly large amount of
oxides, mostly manganese dioxide. Then contact Monona Rossol and ask about
the advisibility of using it. (I would not recommend it)
There is also a black (only when it is still wet) clay made by Plainsman,
H441G, but it fires white.
A web page with information on the hazards and use of manganese has been
made avaiable
by Tony Hansen. Get back to me if you need the address.
aldric3@ibm.net on wed 14 jan 98
I aminterested in locating a supplier of black clay for handbuilding.
Low fire or mid-range would be acceptable. Preferably a supplier near
North Carolina. Thanks,
Cynthia Aldrich aldric3@IBM.Net
Lili Krakowski on sat 17 jan 98
Do yourself a favor. While in some places there still may be doubters
about manganese, reasonable people consider it DANGEROUS.Dec 15 1996 Pat
SHerwood (patsher@trib.com) told a very scary story about one Siglinda
Scarpa who worked barehanded with BLACK CLAY CONTAINING MANGANESE and
within several weeks had central nervous system problems attributed to
the manganese. Now you may be planning to wear gloves, but I have yet to
work with clay without creating particles which turn to dust and no matter
what I do, some gets on my clothes and shoes and ultimately on adorable
little old me! SO WHEN YOU FIND THAT BLACK CLAY SUPPLIER BE SURE TO ASK:
WHAT MAKES THIS CLAY BLACK? And then check that those ingredients are notgoing
ruin your life.
On Wed, 14 Jan 1998
aldric3@ibm.net wrote:
> ----------------------------Original message----------------------------
> I aminterested in locating a supplier of black clay for handbuilding.
> Low fire or mid-range would be acceptable. Preferably a supplier near
> North Carolina. Thanks,
> Cynthia Aldrich aldric3@IBM.Net
>
Lili Krakowski
CNW on tue 22 jun 99
Well a few more questions on manganese. The Clay that I just bought =
(haven't
used yet) is a black stoneware clay from Kickwheel in Atlanta. Way =
expensive
(double my riverside grit =26 earthen red cost) but such a nice color. The =
catalog
refers to a colorant without being specific, and then also mentioned that =
this
is a high iron clay. I had heard that most very dark clays like this used a =
lot
of barnard slip which contains manganese. Is this a problem since it is in =
more
of a more powder form than clays with specks of manganese? Or is my
understanding of getting black color in a clay wrong?
I also need some explanation of glaze descriptions please. I am looking for =
more
textural glazes or at least dry mat. What are the differences between 'dry =
mat'
and 'stoney mat' and plain 'mat'?
One last thing, I have been trying to find out about glaze ingredients =
lately
and read in Chappell's (i think) that strontium is a substitute for barium =
in
most cases, then under strontium it lists whiting as a sub for strontium.
This doesn't make sense to me. Of course I spend most of my time confused.
Celia in NC
cwike=40conninc.com
Ron Roy on thu 24 jun 99
You are right about the high manganese content of Barnard - the analysis I
have says 3.3%. I don't recommend using Manganese in clays unless you take
appropriate precautions and have your blood levels checked regularly.
Sub 3/4 the amount of Strontium for Barium to get the same melt - if the
Barium Carb is 10 then use 7.5 Strontium Carb.
Yes Calcium Carb can be substituted for Barium Carb. I just calculated out
the amount of Whiting to get the same amount of fluxing and it was 1/2 the
amount of Barium. If Barium Carb is 10 then replace with 5 Whiting.
It is interesting to note that because the expansion factors for Barium,
Calcium and Strontium Carb are all similar - because you can get as much
fluxing with lower amounts of SrO and CaO - then you will automatically
lower the expansion of the glaze at the same time.
It should also be kept in mind that adding a small amount of any flux will
give more than expected fluxing - in the other extreme - adding a lot of
one flux like SrO, BaO, CaO, ZnO can have the effect of lowering the
expected fluxing power. Having a combination of fluxes is better than
having one or two for instance - because with the higher fluxing more
silica and alumina can be melted making for more stable and durable glazes.
RR
>----------------------------Original message----------------------------
>Well a few more questions on manganese. The Clay that I just bought (haven't
>used yet) is a black stoneware clay from Kickwheel in Atlanta. Way expensive
>(double my riverside grit & earthen red cost) but such a nice color. The
>catalog
>refers to a colorant without being specific, and then also mentioned that this
>is a high iron clay. I had heard that most very dark clays like this used a lot
>of barnard slip which contains manganese. Is this a problem since it is in more
>of a more powder form than clays with specks of manganese? Or is my
>understanding of getting black color in a clay wrong?
>
>I also need some explanation of glaze descriptions please. I am looking
>for more
>textural glazes or at least dry mat. What are the differences between 'dry
>mat'
>and 'stoney mat' and plain 'mat'?
>
>One last thing, I have been trying to find out about glaze ingredients lately
>and read in Chappell's (i think) that strontium is a substitute for barium in
>most cases, then under strontium it lists whiting as a sub for strontium.
>This doesn't make sense to me. Of course I spend most of my time confused.
>
>Celia in NC
>cwike@conninc.com
Ron Roy
93 Pegasus Trail
Scarborough, Ontario
Canada M1G 3N8
Tel: 416-439-2621
Fax: 416-438-7849
Web page: http://digitalfire.com/education/people/ronroy.htm
Snail Scott on sun 12 nov 00
This stuff is really called Cassius Clay?!? ;o -Snail
At 09:20 PM 11/12/00 EST, you wrote:
>I've worked with Cassius Clay a lot and was always told that the time to
>worry is when the clay is dry (dust), no one has ever said anything about
>when it's firing. I've stopped using old Cassius because it warped and no
>glaze would stick to it. Have you found the secret to Cassius?
>Karin
>
CINDI ANDERSON on sun 12 nov 00
It's actually called Cassius Bassaltic. I haven't had any problems with it. Just
cover with a clear glaze and it's a beautiful color. I wonder how much you have to
use it before any absorption is a problem? Does all black clay have manganese
dioxide?
Cindi
---------
Snail Scott wrote:
> This stuff is really called Cassius Clay?!? ;o -Snail
>
> At 09:20 PM 11/12/00 EST, you wrote:
> >I've worked with Cassius Clay a lot and was always told that the time to
> >worry is when the clay is dry (dust), no one has ever said anything about
> >when it's firing. I've stopped using old Cassius because it warped and no
> >glaze would stick to it. Have you found the secret to Cassius?
> >Karin
> >
>
> ______________________________________________________________________________
> 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.
Karen Sullivan on mon 13 nov 00
Yup.
bamboo karen
I want you to know how much fun I had visiting
the Engrish site, many thanks.
Seems there has been a discussion of two distinctly different
clays. I refered to specifically Aardvark's Cassius Clay, So. Calif.
supplier. I thought it was a clever name for the clay,
which fires jet black. Don't use glaze on it, so I don't
know how it reacts to glaze.
on 11/12/00 9:10 PM, Snail Scott at snail@MINDSPRING.COM wrote:
> This stuff is really called Cassius Clay?!? ;o -Snail
>
>
>
> At 09:20 PM 11/12/00 EST, you wrote:
>> I've worked with Cassius Clay a lot and was always told that the time to
>> worry is when the clay is dry (dust), no one has ever said anything about
>> when it's firing. I've stopped using old Cassius because it warped and no
>> glaze would stick to it. Have you found the secret to Cassius?
>> Karin
>>
>
> ______________________________________________________________________________
> 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.
>
Karin Hurt on mon 13 nov 00
yes, I used to buy it at MidSouth in Nashville and thought they mixed it
themselves. It's wonderful to work with and my bowls turned out fine, but are
strictly non-functional. I made a slab rolled "Smoky Mountain Black Bear" or
did when I lived in TN and out of 50,10 perhaps did not warpe. It also has a
tendency to bubble. I went to MidSouth and asked what was up, I was told to
fire it fast, I've tried fast, slow, med and it made no difference. It's
usually fired at Cone 5 anything lower won't bring out the black.
Karin
CINDI ANDERSON on mon 13 nov 00
I would call it a brownish black. Actually, with a clear glaze it has a nice
pebbly texture with brownish pebbles on the black. I've never had any problems
with warping, and I always fired it at cone 6 oxidation even though I was pressing
my luck because they say to use cone 5 or even cone 4.
Of course now that I've heard here that it warps, mine will. It happens to me
every time I read something here. I say "I've never had that problem" and then I
have it! I swear, this has happened to me a dozen times.
Cindi
----------------
Sarah Dence wrote:
> Cindi, What color is your cassius bassaltic clay after it is fired? Is all
> black clay called cassius bassaltic clay? The reason I ask is that I have
> black clay that I dug from the creek near here and when it is fired to ^06
> it is orange! the first time I opened my kiln I was sssoooo surprised!
> _________________________________________________________________________
> Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.
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>
> You may look at the archives for the list or change your subscription
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>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
Sarah Dence on mon 13 nov 00
Cindi, What color is your cassius bassaltic clay after it is fired? Is all
black clay called cassius bassaltic clay? The reason I ask is that I have
black clay that I dug from the creek near here and when it is fired to ^06
it is orange! the first time I opened my kiln I was sssoooo surprised!
_________________________________________________________________________
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Larry Phillips on mon 13 nov 00
Sarah Dence wrote:
>
> Cindi, What color is your cassius bassaltic clay after it is fired? Is all
> black clay called cassius bassaltic clay? The reason I ask is that I have
> black clay that I dug from the creek near here and when it is fired to ^06
> it is orange! the first time I opened my kiln I was sssoooo surprised!
I have used a raku clay that is black until bisqued, at which time it's
a pale pinkish colour. I can't recall who makes it. Perhaps plainsman or
Laguna.
--
Hukt on fonix werkt fer me!
http://cr347197-a.surrey1.bc.wave.home.com/larry/
Snail Scott on mon 13 nov 00
Lots of clays are black or colored when dug, but not after firing.
This is because the color wasn't due to oxides, but to organics
which burned out. This is not the case with so-called basaltic clays.
-Snail
At 10:39 AM 11/13/00 CST, you wrote:
>Cindi, What color is your cassius bassaltic clay after it is fired? Is all
>black clay called cassius bassaltic clay? The reason I ask is that I have
>black clay that I dug from the creek near here and when it is fired to ^06
>it is orange! the first time I opened my kiln I was sssoooo surprised!
>_________________________________________________________________________
>Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.
>
>Share information about yourself, create your own public profile at
>http://profiles.msn.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.
>
Karen Sullivan on tue 14 nov 00
Cassius Clay comes from Aardvark Clay & Supplies
1400 E. Pomona St., Santa Ana, CA 92705-4812
714-541-4157 or fax 714-541-2021
Cassius Basaltic Clay
The folks at Aardvark are great to work with.
bamboo karen
on 11/14/00 12:47 PM, Mayssan1@AOL.COM at Mayssan1@AOL.COM wrote:
> Hi,
> Where does one order Cassius Clay?
> It sounds interesting,
> Thank you
> Mayssan
>
> ______________________________________________________________________________
> 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.
>
scott lykens on tue 14 nov 00
sometimes the brick clay at watershed center for the ceramic arts (generally
dark grey) is black. it also bisques orange. it fires out to a rich terra
cotta red at cone 04, gets redder unless you fire it in reduction then its
metalic brown red.
>From: Sarah Dence
>Reply-To: Ceramic Arts Discussion List
>To: CLAYART@LSV.CERAMICS.ORG
>Subject: Re: black clay
>Date: Mon, 13 Nov 2000 10:39:20 CST
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>Cindi, What color is your cassius bassaltic clay after it is fired? Is all
>black clay called cassius bassaltic clay? The reason I ask is that I have
>black clay that I dug from the creek near here and when it is fired to ^06
>it is orange! the first time I opened my kiln I was sssoooo surprised!
>_________________________________________________________________________
>Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.
>
>Share information about yourself, create your own public profile at
>http://profiles.msn.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.
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Karin Hurt on tue 14 nov 00
Cassius Clay fires pitch black at Cone 5.
Janet Kaiser on tue 14 nov 00
There are also clays which have dyes added to
help distinguish them and keep apart either in
the factory or in the studio. I do not know
off-hand which, but Potclays produce a lurid
green! Burns out entirely of course.
Janet Kaiser
The Chapel of Art . Capel Celfyddyd
HOME OF THE INTERNATIONAL POTTERS' PATH
Criccieth LL52 0EA, GB-Wales Tel: (01766) 523570
E-mail: postbox@the-coa.org.uk
WEBSITE: http://www.the-coa.org.uk
----- Original Message -----
> Lots of clays are black or colored when dug,
but not after firing.
> This is because the color wasn't due to
oxides, but to organics
> which burned out. This is not the case with
so-called basaltic clays.
Mayssan1@AOL.COM on tue 14 nov 00
Hi,
Where does one order Cassius Clay?
It sounds interesting,
Thank you
Mayssan
Milton Markey on tue 14 nov 00
Hi All You Black Clay Fans, and other interested lurkers!
I use another clay, made by IMCO, near Sacramento, CA, called Black
Mountain. In the bag, it's a deep brown clay. It has a super smooth texture,
which makes it easy for wheel potters and hand builders alike.
Like Cassius Basaltic, it contains a lot of iron, manganese, and titanium,
which contribute to it's "black" fired nature. When fired to cone 10,
reduction, the clay becomes a solid black, stony (semi-gloss)textured clay. I
can't recommend this clay for oxydation firing, since doing so produces a
deep brown, not black, matte textured clay.
One caveat, which applies to both Black Mountain, and Cassius Basaltic: fire
these clays slowly, and reduce heavily. Both clays tend to bloat over cone
10. If fact, I've fired Black Mountain to cone 9, in order to prevent
bloating that might occur at its vitrifying point.
Best wishes!
Milton NakedClay@AOL.COM
Not naked today--a wintery cold spell has cast a chilly time here in the
Mojave! The local stores have run out of thermal underware!
Milton Markey on wed 15 nov 00
In a message dated 11/14/00, Mayssan writes:
> Hi,
> Where does one order Cassius Clay?
> It sounds interesting,
============================
Hi Mayssan!
Order Cassius Basaltic Clay from Aardvark, in Santa Ana, CA.
Phone: 714-541-4157
Milton NakedClay@AOL.COM
iandol on thu 16 nov 00
The idea of a black clay, be it natural as found or a manufactured one, =
is intriguing especially when it changes to a good terra cotta =
red/orange on firing. I suspect some interesting chemistry at work here.
Thinking in a speculative manner, the black discolouration of the =
natural clay may be due to organic contamination in the form of lignite =
or finely divided coal or it may be due to iron sulphide. Red after =
firing certainly suggests a lot of iron. So if it is a smooth fine =
grained clay it may also have uses as a glaze ingredient for one of =
those natural celadons.
Now a black compounded body from the store? Well the nature of the black =
is for any one to have a guess about.
Whatever the cause of the black colour of the raw clay, it will need a =
slow firing with plenty of air.
Regards,
Ivor
=20
Karin Hurt on thu 16 nov 00
I bought my Cassius at Mid-South in Nashville, TN
Brenda Beeley on thu 16 nov 00
A potter friend of mine uses Cassius Clay with cone 5 Laguna glazes---they
break beautifully on her highly patterned ware showing the black through
it.
Brenda
Bruce Girrell on thu 16 nov 00
Ivor Lewis wrote:
>The idea of a black clay, be it natural as found or a manufactured one, is
intriguing
>especially when it changes to a good terra cotta red/orange on firing. I
suspect some
>interesting chemistry at work here.
A couple of years ago on a trip to the American Southwest, Lynne and I saw
some heavily cracked soil near the side of the road. We gathered some of it,
gave it a spit test, and found it to be a very fine grained clay. When we
returned, we tried using some, but it appears to be a smectite and the
shrinkage was way too high. It was also very difficult to hydrate
completely.
We have used it as a slip and it fired to a warm orangey-brown - a very
pleasant color, but not what you'd expect from black.
>Thinking in a speculative manner, the black discolouration of the natural
clay may be
>due to organic contamination in the form of lignite or finely divided coal
or it may be >due to iron sulphide. Red after firing certainly suggests a
lot of iron.
I came to the same conclusions (so if it turns out that we're wrong, at
least we have company).
>So if it is a smooth fine grained clay it may also have uses as a glaze
ingredient for >one of those natural celadons.
Hadn't thought about that. I was just cleaning up our studio area and nearly
pitched the remaining bags of this stuff. Now you're going to make me keep
it. It's all _your_ fault. :-{)> [smiley with moustache and beard]
Bruce Girrell in northern Michigan
where the snow has finally arrived. The last show for this year is done
(People liked our stuff!!! They asked questions and said nice things even
when they didn't have to!). I have a list of at least three major
experiments to run, and the shows plus Christmas gifts have completely
depleted our inventory, so there's no danger of running out of things to do.
There's no end to this clay endeavor, is there? (I hope not)
Wagtime on tue 24 apr 01
Am I flogging a dead horse in attempting to apply a white underglaze to
black clay that is fired to cone 5? The black bleeds through at this
temperature. If I reapply white underglaze and refire to a lower
temperature, is there a temperature (say 06) where the chemical content of
the black clay will not affect.
Ultimately I want a gloss finish on the white.
Unfortunately I don't have a test kiln and this is not the firing range I
usually work in, otherwise I'd experiment in all directions. Any help or
suggestions would be greatly appreciated. Thankyou in advance....
Ababi on tue 24 apr 01
Sometime ago I was a painter. I loved to paint with pastels. sometime s
acrylic. I knew to use the color of the paper.
I knew that brown paper will effect the green leaves different than white
or red paper.
What you want to do , is to take a dark clay, probably fool with manganese
and want it to behave like clean porcelain?
This clay you have, has it's uses. It probably will react wonderful with
glazes, try majolica bases, they contains a lot of "white" anyway. Add 4-6
copper oxide
or 5-10iron oxide.
I do not have a test kiln too. For every firing to ^6 .which is happening
about once a month I prepare tests.
Now, this clay, you can try,carefully to fire to ^6, above a plate, may be
black like charcoal!
I live in a primitive country where sometimes, not always, we use the same
claybody for high, and low fire as it is written 1100-1250C. Try to use it
in low fire, or keep it for "better days"- for this clay!
Ababi, away from the pasificcoast!
(Sometimes wish to be there)
Ababi Sharon
ababisha@shoval.ardom.co.il
http://members4.clubphoto.com/ababi306910/
----- Original Message -----
From: "Wagtime"
To:
Sent: Tuesday, April 24, 2001 5:33 PM
Subject: Black Clay
> Am I flogging a dead horse in attempting to apply a white underglaze to
> black clay that is fired to cone 5? The black bleeds through at this
> temperature. If I reapply white underglaze and refire to a lower
> temperature, is there a temperature (say 06) where the chemical content
of
> the black clay will not affect.
> Ultimately I want a gloss finish on the white.
>
> Unfortunately I don't have a test kiln and this is not the firing range I
> usually work in, otherwise I'd experiment in all directions. Any help or
> suggestions would be greatly appreciated. Thankyou in advance....
>
>
____________________________________________________________________________
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> Send postings to clayart@lsv.ceramics.org
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melpots@pclink.com.
>
alex wise on mon 30 apr 01
Milton:
I use Kickwheel's Raven Black (#333); I find that kilnwash does a super j=
ob
as a white 'slip' and it is truely white against the black.
Lesley
VB
marianne kuiper milks on tue 14 mar 06
I am looking for a recipe to make black (or really deep coca-brown) clay. I couldn't find anything in the archives. can someone help me??
Marianne
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Bob Hanlin on wed 15 mar 06
Several...well maybe many years ago...Aardvark Clay stocked a clay called "Cassius Basaltic". It fired to a true black at cone 5 oxidation. Lower it was dark, dark brown; higher (as I recall) it bloated. I used it for a while with great results.
I heard about it at a workshop with Virginia Cartwright...what ever happened to her?
Bob Hanlin
OKC
Steve Slatin on thu 16 mar 06
I bought some "cassius clay" (nyuck nyuck) just
last year, so I guess it's still available. It
threw well and so on but stained the living
daylights out of everything it touched -- canvas,
plaster wedging block, etc. I didn't get
bloating, but I don't go over a somewhat 'hard'
cone 6.
-- Steve Slatin
--- Bob Hanlin wrote:
> Several...well maybe many years ago...Aardvark
> Clay stocked a clay called "Cassius Basaltic".
> It fired to a true black at cone 5 oxidation.
> Lower it was dark, dark brown; higher (as I
> recall) it bloated.
Steve Slatin --
In the mornin’ cry of the rooster
The baby lay alone
And the old cow in the green grass
Shed white tears in the red hot sun
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