Badlands Pottery on fri 3 mar 00
I only got one response, so I thought I would try again. The Reitz green
glaze has turned brown in the last three firings, although the firings
turned out really well. That was the only glaze that had problems. It did
really well when I initially mixed it up. I've been told that I should add
5-10% more gerstley. Any validity to that? Any other suggestions? Here's
the recipe:
Neph Sye 70
Whiting 5
Gerstley Borate 2
Petalite 15
OM-4 Ball Clay 8
Cobalt Carb 1
Rutile 1
Thanks in advance. Lori
______________________________________________________
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Hank Murrow on sat 4 mar 00
>----------------------------Original message----------------------------
>I only got one response, so I thought I would try again. The Reitz green
>glaze has turned brown in the last three firings, although the firings
>turned out really well. That was the only glaze that had problems. It did
>really well when I initially mixed it up. I've been told that I should add
>5-10% more gerstley. Any validity to that? Any other suggestions? Here's
>the recipe:
>
>Neph Sye 70
>Whiting 5
>Gerstley Borate 2
>Petalite 15
>OM-4 Ball Clay 8
>Cobalt Carb 1
>Rutile 1
>
>Thanks in advance. Lori
Dear Lori; I agree with the previous post concerning this problem; that is,
you may be getting it on too thin. Another issue may be the iron content of
the clay you use. This glaze likes iron-free bodies to develop the best
green color, so try a white or porcelainous body. Hank in Eugene
Llewellyn on sat 4 mar 00
Dear Lori,
I would also like to know about the Reitz green. I tried it in several test
kilns and nothing to my likes. I would be interested to know if it should
have more gerstley in? Maybe I should give this one a retry? I really like
it in pictures in books but when I give it a go - it is not a nice glaze in
either melt? or color.
Llewellyn
ABBEY POTTERY
http://www.assumptionabbey.com/Pottery
----- Original Message -----
From: "Badlands Pottery"
To:
Sent: March 03, 2000 9:48 AM
Subject: HELP!! Reitz Green Problem
> ----------------------------Original message----------------------------
> I only got one response, so I thought I would try again. The Reitz green
> glaze has turned brown in the last three firings, although the firings
> turned out really well. That was the only glaze that had problems. It
did
> really well when I initially mixed it up. I've been told that I should
add
> 5-10% more gerstley. Any validity to that? Any other suggestions?
Here's
> the recipe:
>
> Neph Sye 70
> Whiting 5
> Gerstley Borate 2
> Petalite 15
> OM-4 Ball Clay 8
> Cobalt Carb 1
> Rutile 1
>
> Thanks in advance. Lori
> ______________________________________________________
> Get Your Private, Free Email at http://www.hotmail.com
Janet Harper on sat 4 mar 00
In a message dated 3/3/00 1:00:16 PM Eastern Standard Time,
badlandspottery@hotmail.com writes:
<< -----------------------Original message----------------------------
I only got one response, so I thought I would try again. The Reitz green
glaze has turned brown in the last three firings, although the firings
turned out really well. That was the only glaze that had problems. It did
really well when I initially mixed it up. I've been told that I should add
5-10% more gerstley. Any validity to that? Any other suggestions? Here's
the recipe:
Neph Sye 70
Whiting 5
Gerstley Borate 2
Petalite 15
OM-4 Ball Clay 8
Cobalt Carb 1
Rutile 1
Thanks in advance. Lori
____________ >>
Lori,
My experience with this glaze in ^10 reduction is that it is green when
applied thick and brown where thin. Have you tried siphoning off some of the
water in the glze bucket before you mix it?
Good luck,
Janet
Mark Mondloch on sun 5 mar 00
Lori,
Don't really have an answer for you, maybe just more questions. I've been
trying adjustments to this glaze for a while to try to eliminate little
pinholes when fired in the gas kiln. Things that didn't work-
-upping the whiting a bit (dry, scratchy and blue)
-adding small amount of wood-ash( tried this because it comes out smoother in
the wood kiln but made for more pin-holes in the gas kiln)
The load I just unpacked had the following test. I replaced the whiting with
wollastonite to eliminate possible gassing problems and replaced the petalite
with spodumene for a lower melt temp. and to bring the silica back down from
the wollastonite addition.
cobalt green c10-variation2/00
==============================
GERSTLEY BORATE..... 2.00 2.00%
NEPHELINE SYENITE... 70.00 70.00%
BALL CLAY........... 8.00 8.00%
rutile.............. 1.00 1.00%
*cobalt carb......... 1.00 1.00%
SPODUMENE........... 12.00 12.00%
WOLLASTONITE........ 6.00 6.00%
========
100.00
CaO 0.24* 3.59%
Li2O 0.12* 0.94%
MgO 0.00* 0.04%
K2O 0.14* 3.55%
Na2O 0.49* 7.91%
TiO2 0.05 1.14%
ZrO2 0.00 0.01%
Al2O3 0.85 22.77%
B2O3 0.06 1.07%
SiO2 3.74 58.85%
Fe2O3 0.00 0.13%
Cost/kg 0.64
Si:Al 4.39
SiB:Al 4.46
Expan 8.54
The tests with this were very nice and smooth, but the color had shifted to
more of a dark teal then the very green of the original. I'm going to try this
recipe with 1.5 rutile next load to try to get the green back
Other observations- The color on the original recipe has been more muted(
closer to brown) on loads that were more heavily reduced but the surface seems
smoother in those loads. Tests in the little electric test kiln were always
very green and nice and smooth. Pieces raw glazed are very pinholed in the gas
kiln, usually smooth in the wood kiln.
I haven't tried upping the gerstley. Let us know what happens.
Sylvia
Badlands Pottery wrote:
> ----------------------------Original message----------------------------
> I only got one response, so I thought I would try again. The Reitz green
> glaze has turned brown in the last three firings, although the firings
> turned out really well. That was the only glaze that had problems. It did
> really well when I initially mixed it up. I've been told that I should add
> 5-10% more gerstley. Any validity to that? Any other suggestions? Here's
> the recipe:
>
> Neph Sye 70
> Whiting 5
> Gerstley Borate 2
> Petalite 15
> OM-4 Ball Clay 8
> Cobalt Carb 1
> Rutile 1
>
> Thanks in advance. Lori
> ______________________________________________________
--
Mark & Sylvia Mondloch
Silver Creek Pottery & Forge
W6725 Hwy 144
Random Lake, WI 53075
silvercreek@execpc.com
http://www.execpc.com/silvercreek
Hank Murrow on sun 5 mar 00
><< -----------------------Original message----------------------------
> I only got one response, so I thought I would try again. The Reitz green
> glaze has turned brown in the last three firings, although the firings
> turned out really well. That was the only glaze that had problems. It did
> really well when I initially mixed it up. I've been told that I should add
> 5-10% more gerstley. Any validity to that? Any other suggestions? Here's
> the recipe:
>
> Neph Sye 70
> Whiting 5
> Gerstley Borate 2
> Petalite 15
> OM-4 Ball Clay 8
> Cobalt Carb 1
> Rutile 1
>
> Thanks in advance. Lori
> ____________ >>
> Lori,
>
>My experience with this glaze in ^10 reduction is that it is green when
>applied thick and brown where thin. Have you tried siphoning off some of the
>water in the glze bucket before you mix it?
>
>Good luck,
>Janet
And Lori; For the best green try 2 per cent Rutile. Hank in Eugene
Ray Aldridge on tue 7 mar 00
At 12:48 PM 3/3/00 EST, you wrote:
>----------------------------Original message----------------------------
>I only got one response, so I thought I would try again. The Reitz green
>glaze has turned brown in the last three firings, although the firings
>turned out really well. That was the only glaze that had problems. It did
>really well when I initially mixed it up. I've been told that I should add
>5-10% more gerstley. Any validity to that? Any other suggestions? Here's
>the recipe:
>
>Neph Sye 70
>Whiting 5
>Gerstley Borate 2
>Petalite 15
>OM-4 Ball Clay 8
>Cobalt Carb 1
>Rutile 1
>
Lori, I think someone else mentioned this, but my guess is that it's a
thickness problem-- you're putting it on too thin and the clay body is
burning through. Have you experimented with different thicknesses? I'm
assuming here that you're using a clay that has a fair amount of brown in it.
Ray
Aldridge Porcelain and Stoneware
http://www.goodpots.com
Katie Ferguson on fri 10 mar 00
Lori,
Hi With some of my glazes I have a weird problem like that too! I have a
blue glaze that is supposed to be like a country blue but turns out greenish
when I fire differently. Sometimes if I fire it longer on the different temp.
ranges I get better color. this depends of coarse on what type of kiln you
have, mine is electric! So you might want to experiment with it!! Hope this
helps:)
~Katie~
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