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cone 6 red glaze...

updated sat 14 apr 07

 

Paul Lewing on thu 12 apr 07


As others have said, this glaze has almost no alumina and not much
silica, so it's probably not real durable. On the other hand,
there's not much in it that would hurt most people. Note that I said
MOST people. Some people, Ron Roy among them, have a medical
condition that makes ingesting iron harmful to them. And if this
sucker is going to leach anything, it's going to be all that iron.
And totally aside from leaching something harmful into someone's
body, customers will not like it if it changes color.
Paul Lewing
www.paullewingtile.com

Lori Doty on thu 12 apr 07


Hi all,

I have a cone 6 glaze called OX Blood Red that I just tried on my
cone 6 porcelain that looks good almost luscious. No crazing and
visually looks like a red oil spot glaze. I also want the opinion of
those of you that know glazes if you think this is a stable food safe
glaze, I am reading and rereading my copy of R&J's MC6G but so far
have not gained enough insight into this to really know. I am
currently doing a vinegar soak so I shall see if there are disastrous
results in 24 or less hours.

Here is the recipe:
Ingredient 100 gram batch
Gerstley Borate 55
Talc 15
Flint 30
100 total

now add RIO 22

So for those of you that may be willing to help me out I appreciate
it before I commit a whole kiln load of pots to this.

Lori Doty
Nurse/Potter
Rolla, MO

Where it has stopped raining and the sun came out this afternoon
while I was at work and the trees look like they just might survive
the last two freezing cold weeks

William & Susan Schran User on thu 12 apr 07


On 4/12/07 8:10 PM, "Lori Doty" wrote:

> I also want the opinion of
> those of you that know glazes if you think this is a stable food safe
> glaze, I am reading and rereading my copy of R&J's MC6G but so far
> have not gained enough insight into this to really know. I am
> currently doing a vinegar soak so I shall see if there are disastrous
> results in 24 or less hours.
>
> Here is the recipe:
> Ingredient 100 gram batch
> Gerstley Borate 55
> Talc 15
> Flint 30
> 100 total
>
> now add RIO 22

Even before running this through glaze calculation software, I would be very
suspicious of this glaze as it contains no clay.


--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com

Angela Davis on thu 12 apr 07


Hi Lori, your Ox Blood glaze sounds like a glaze we
mix at school we call "Alyssa's Floating Red".
I read Alyssa's test of it on Clayart and had to give it a try.

It is nice and red with patches of warm brown where
thin. We use it a lot over clay with heavy texture where

----- Original Message -----
From: "Lori Doty"
To:
Sent: Thursday, April 12, 2007 7:10 PM
Subject: Cone 6 red glaze...


> Hi all,
>
> I have a cone 6 glaze called OX Blood Red that I just tried on my
> cone 6 porcelain that looks good almost luscious. No crazing and
> visually looks like a red oil spot glaze. I also want the opinion of
> those of you that know glazes if you think this is a stable food safe
> glaze, I am reading and rereading my copy of R&J's MC6G but so far
> have not gained enough insight into this to really know. I am
> currently doing a vinegar soak so I shall see if there are disastrous
> results in 24 or less hours.
>
> Here is the recipe:
> Ingredient 100 gram batch
> Gerstley Borate 55
> Talc 15
> Flint 30
> 100 total
>
> now add RIO 22
>
> So for those of you that may be willing to help me out I appreciate
> it before I commit a whole kiln load of pots to this.
>
> Lori Doty
> Nurse/Potter
> Rolla, MO
>
> Where it has stopped raining and the sun came out this afternoon
> while I was at work and the trees look like they just might survive
> the last two freezing cold weeks
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
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>
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> melpots@pclink.com.
>
>
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> 11:52 AM
>
>

Ron Roy on fri 13 apr 07


This is hardly worth calling a glaze - .02 alumina and 1.75 silica will
make for a very unstable glaze - leave a piece of soap on it over night and
see what happens - or a slice of lemon.

I'm not saying it cannot be used in a decorative way but - without the iron
it shows a low calculated expansion - hard to tell if it's dangerous as
that much boron and it does not lower expansion as much as you might think.

RR

>Hi all,
>
>I have a cone 6 glaze called OX Blood Red that I just tried on my
>cone 6 porcelain that looks good almost luscious. No crazing and
>visually looks like a red oil spot glaze. I also want the opinion of
>those of you that know glazes if you think this is a stable food safe
>glaze, I am reading and rereading my copy of R&J's MC6G but so far
>have not gained enough insight into this to really know. I am
>currently doing a vinegar soak so I shall see if there are disastrous
>results in 24 or less hours.
>
>Here is the recipe:
>Ingredient 100 gram batch
>Gerstley Borate 55
>Talc 15
>Flint 30
> 100 total
>
>now add RIO 22
>
>So for those of you that may be willing to help me out I appreciate
>it before I commit a whole kiln load of pots to this.
>
>Lori Doty
>Nurse/Potter
>Rolla, MO
>
>Where it has stopped raining and the sun came out this afternoon
>while I was at work and the trees look like they just might survive
>the last two freezing cold weeks
>
>______________________________________________________________________________
>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.

Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0

claystevslat on fri 13 apr 07


Lori -- I hate to be repetitive on this, but
the only way to be sure that a glaze/clay
combination is safe is to test it. MC6G
test procedures are pretty simple, inexpensive,
and not unreasonably time consuming. If your
glaze holds up to vinegar, it'll hold up to
virtually all foods.

If you leave a pot with that glaze in a dishwasher
for a few months (just let it cucle through over
and over) you'll see if it holds up to alkali
attack.

If you eyeball the glaze, you'll see it's rather
low on silica, and extremely low on alumina. At
^6 ox., RIO is a refractory -- this may be why
this glaze doesn't just flow right off the pot
at ^6.

Glazes that are outside the normal range sometimes
have the most interesting effects. Please post and
tell us what happens in your test.

-- Steve Slatin


--- In clayart@yahoogroups.com, Lori Doty wrote:
>
> Hi all,
>
> I have a cone 6 glaze called OX Blood Red that I just tried on my
> cone 6 porcelain that looks good almost luscious. No crazing and
> visually looks like a red oil spot glaze. I also want the opinion
of
> those of you that know glazes if you think this is a stable food
safe
> glaze, I am reading and rereading my copy of R&J's MC6G but so far
> have not gained enough insight into this to really know. I am
> currently doing a vinegar soak so I shall see if there are
disastrous
> results in 24 or less hours.
>
> Here is the recipe:
> Ingredient 100 gram batch
> Gerstley Borate 55
> Talc 15
> Flint 30
> 100 total
>
> now add RIO 22
>
> So for those of you that may be willing to help me out I appreciate
> it before I commit a whole kiln load of pots to this.
>
> Lori Doty

Don Goodrich on fri 13 apr 07


Hi Lori,
One would think that that glaze, with essentially no alumina, wouldn't
be durable. However, I happen to have glazed a stoneware jug with that
recipe in 1996. It turned out pretty ugly, probably because in large areas
the glaze was too thin and turned a sickly brown. The red areas do indeed
look like blood poured on the pot. This jug has been in regular use for
eleven years (I water houseplants with it), and the glaze has held up very
well. However, it doesn't get washed very often so your mileage may vary.

Since there's nothing normally toxic in it, I'd say go ahead and use it,
especially on porcelain exteriors where it will be safe and not look
ghastly.
Hope you can put up some pix to inspire us.

Cheers,
Don Goodrich

http://dongoodrichpottery.com/