Barb Lund on thu 26 nov 98
thanks to you, dear clayarters, I tried 3 new glazes that were posted
recently and I really l;ike them. Now, likewise dear glaze experts, may I
use them on stoneware for dinnerware etc.
Noxema bottle blue ^6
custer spar 38.1
dolomite 10
epk 9.6
silica 9.5
zinc ox 9.4
cob carb 3.5
looked great with
Pink Icing version 3 on top
gerstley 6.2
lithium 2
mag carb 6.1
strontium carb 12.6
whiting 12.1
neph sy 21
flint 40
---------
tin ox 3
powdered rutile 3.6
Oil Spot-shiny black
epk 9.5
custer spar 152.6
whiting 10.6
gerstley 20.8
copper carb 8
manganese 8
cobalt ox 4
I have my suspicions about the black because there is so much manganese in
it but it is a lovely shiny rich black! thanks to those who posted these
recipes and TIA to those who will tell me if I can use them freely or Not
Gobble Gobble!
Other Barb in Bloomington barblund@bluemarble.net
ps I know very little about glaze chemistry but I can follow a recipe!
Laurel Carey on fri 27 nov 98
Barb Lund wrote:
>
> ----------------------------Original message----------------------------
> thanks to you, dear clayarters, I tried 3 new glazes that were posted
> recently and I really l;ike them. Now, likewise dear glaze experts, may I
> use them on stoneware for dinnerware etc.
>
(snip)
> Oil Spot-shiny black
> epk 9.5
> custer spar 152.6
> whiting 10.6
> gerstley 20.8
> copper carb 8
> manganese 8
> cobalt ox 4
>
> I have my suspicions about the black because there is so much manganese in
> it but it is a lovely shiny rich black! thanks to those who posted these
> recipes and TIA to those who will tell me if I can use them freely or Not
>
> Gobble Gobble!
>
> Other Barb in Bloomington barblund@bluemarble.net
> ps I know very little about glaze chemistry but I can follow a recipe!
i was the one who posted this oilspot glaze, my teacher at school said
it was safe, and recommended it to everyone. (!) *however* i have been
told in response to my post that it is NOT food safe. i was told by ron
roy and tom buck and i thank them. due to my teacher's recommendation i
had some bowls with this glaze in use for years...(sigh)
yer right, it is a pretty glaze tho...try layering it with other glazes,
this seems to make the colorants separate, and you get really
interesting blue and beige streaks.
laurel
lacarey@ioa.com
asheville, nc, usa
John Hesselberth on sat 28 nov 98
Hi Barb,
I haven't compared any of these glazes with the limit formulas; however
there is no way I would use the Oil spot-shiny black with food without
having it tested for manganese, copper and cobalt leaching. Copper is
very difficult to keep in solution and 8% is a huge amount. If it leaches
more than 10 ppm it will give orange juice a bitter taste. Wouldn't
surprise me a bit if this would leach 50-100 ppm. Cobalt is relatively
easy to keep in solution; however, again, 4% is a lot. I don't have any
experience with manganese. If you want to have your glaze tested you can
find instructions on Tony Hansen's web site at http://www.digitalfire.com
or on my web site at http://www.frogpondpottery.com/glazetest
Barb Lund wrote:
>----------------------------Original message----------------------------
>thanks to you, dear clayarters, I tried 3 new glazes that were posted
>recently and I really l;ike them. Now, likewise dear glaze experts, may I
>use them on stoneware for dinnerware etc.
>
>Noxema bottle blue ^6
>custer spar 38.1
>dolomite 10
>epk 9.6
>silica 9.5
>zinc ox 9.4
>cob carb 3.5
>
>looked great with
>Pink Icing version 3 on top
>gerstley 6.2
>lithium 2
>mag carb 6.1
>strontium carb 12.6
>whiting 12.1
>neph sy 21
>flint 40
>---------
>tin ox 3
>powdered rutile 3.6
>
>
>Oil Spot-shiny black
>epk 9.5
>custer spar 152.6
>whiting 10.6
>gerstley 20.8
>copper carb 8
>manganese 8
>cobalt ox 4
>
>I have my suspicions about the black because there is so much manganese in
>it but it is a lovely shiny rich black! thanks to those who posted these
>recipes and TIA to those who will tell me if I can use them freely or Not
>
>Gobble Gobble!
>
>Other Barb in Bloomington barblund@bluemarble.net
>ps I know very little about glaze chemistry but I can follow a recipe!
John Hesselberth
Frog Pond Pottery
P.O. Box 88
Pocopson, PA 19366 USA
EMail: john@frogpondpottery.com web site: http://www.frogpondpottery.com
"The whole aim of practical politics is to keep the populace alarmed, and
hence clamorous to be led to safety, by menacing it with an endless
series of hobgoblins, all of them imaginary." H.L. Mencken, 1925
Ron Roy on wed 2 dec 98
Hi Barb, I've been busy with family stuff which explains why I'm so late
with this.
The Nox Blue is a little short of silica and a lot over with ZnO - could
this be a matte glaze? There is more copper than is recommended so I would
bet it is giving up more than you really want it to. If I add silica to
make it better it will go shiny - and become more durable.
Pink - a little short of silica and way short of alumina - but nothing
terrible present - must be a bitch to keep stirred up though - Because
there is so little alumina I would expect it would be susceptible to
changing over time because alkalies will have an effect - just leave a tile
or something in the dish washer for a month and then compare it to an
untreated sample.
Oil spot - this is a difficult one - I think I have even commented on it
already but just in case I left something out. When I calculate this the
silica and alumina are quite high - then I include the MnO2 as flux they
both go down of course - trouble is I can't include the fluxing of the
cobalt and copper cause I don't have them in my calculator - but I do know
they are helping the melt - just how much I don't know - I have to assume -
as John already has - that this glaze is going to give up some of it's
stuff and would not recommend it where food will be.
You should do some testing yourself and perhaps get Alfred to tell you how
much copper and cobalt are coming out - we all want to know! Well maybe not
everyone - regards - RR
>Noxema bottle blue ^6
>custer spar 38.1
>dolomite 10
>epk 9.6
>silica 9.5
>zinc ox 9.4
>cob carb 3.5
>
>looked great with
>Pink Icing version 3 on top
>gerstley 6.2
>lithium 2
>mag carb 6.1
>strontium carb 12.6
>whiting 12.1
>neph sy 21
>flint 40
>---------
>tin ox 3
>powdered rutile 3.6
>
>
>Oil Spot-shiny black
>epk 9.5
>custer spar 152.6
>whiting 10.6
>gerstley 20.8
>copper carb 8
>manganese 8
>cobalt ox 4
>
>I have my suspicions about the black because there is so much manganese in
>it but it is a lovely shiny rich black! thanks to those who posted these
>recipes and TIA to those who will tell me if I can use them freely or Not
>
>Gobble Gobble!
>
>Other Barb in Bloomington barblund@bluemarble.net
>ps I know very little about glaze chemistry but I can follow a recipe!
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
Barb Lund on fri 4 dec 98
Hi ron, glad to hear from you! the Noxema blue is very shiny and indeed
looks just like a noxema bottle. It doesn't seem to run although the
person who posted the recipe said it would. If you, in your free time
(hah) would care to make it a more stable glze, I would be thrilled. I
would like to put it on dinnerware perhaps with the pink. I'll only do
much of this if there is a good public response. The black would have been
nice but I'll just put that on decorative stuff. Thanks you so much for
being here! other Barb in Bloomington
At 05:48 PM 12/2/98 EST, you wrote:
>----------------------------Original message----------------------------
>Hi Barb, I've been busy with family stuff which explains why I'm so late
>with this.
>
>The Nox Blue is a little short of silica and a lot over with ZnO - could
>this be a matte glaze? There is more copper than is recommended so I would
>bet it is giving up more than you really want it to. If I add silica to
>make it better it will go shiny - and become more durable.
>
>Pink - a little short of silica and way short of alumina - but nothing
>terrible present - must be a bitch to keep stirred up though - Because
>there is so little alumina I would expect it would be susceptible to
>changing over time because alkalies will have an effect - just leave a tile
>or something in the dish washer for a month and then compare it to an
>untreated sample.
>
>Oil spot - this is a difficult one - I think I have even commented on it
>already but just in case I left something out. When I calculate this the
>silica and alumina are quite high - then I include the MnO2 as flux they
>both go down of course - trouble is I can't include the fluxing of the
>cobalt and copper cause I don't have them in my calculator - but I do know
>they are helping the melt - just how much I don't know - I have to assume -
>as John already has - that this glaze is going to give up some of it's
>stuff and would not recommend it where food will be.
>
>You should do some testing yourself and perhaps get Alfred to tell you how
>much copper and cobalt are coming out - we all want to know! Well maybe not
>everyone - regards - RR
>
>
>>Noxema bottle blue ^6
>>custer spar 38.1
>>dolomite 10
>>epk 9.6
>>silica 9.5
>>zinc ox 9.4
>>cobalt carb 3.5
>>
>>looked great with
>>Pink Icing version 3 on top
>>gerstley 6.2
>>lithium 2
>>mag carb 6.1
>>strontium carb 12.6
>>whiting 12.1
>>neph sy 21
>>flint 40
>>---------
>>tin ox 3
>>powdered rutile 3.6
>>
>>
>>Oil Spot-shiny black
>>epk 9.5
>>custer spar 152.6
>>whiting 10.6
>>gerstley 20.8
>>copper carb 8
>>manganese 8
>>cobalt ox 4
>>
>>I have my suspicions about the black because there is so much manganese in
>>it but it is a lovely shiny rich black! thanks to those who posted these
>>recipes and TIA to those who will tell me if I can use them freely or Not
>>
>>Gobble Gobble!
>>
>>Other Barb in Bloomington barblund@bluemarble.net
>>ps I know very little about glaze chemistry but I can follow a recipe!
>
>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
>
john a gibson on sat 5 dec 98
Ron and Barb, I have also tried this glaze and found it to be a matt
glaze as you said it would be Ron. I have 2 questions for you Ron, first
, since I am in the same situation as Barb, I can follow the recipe but
have no chem background, how would you calculate additions to arrive at
additional silica. I could use this info to work with other glaze
fomulas. Secondly, how is copper involved in this formula since it is not
mentioned in the nox blu formula? I only find copper in the black form.
which you said was not safe . Once getting a good looking shiny blue I
plan to submit to Alfred for analysis. I appreciate any help. Thanks,
Barb , I am an old Hoosier living in Va. You live in a beautiful part of
the state, I enjoy reading your posts. Take care JOHN.
___________________________________________________________________
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com/getjuno.html
or call Juno at (800) 654-JUNO [654-5866]
| |
|
