Lili Krakowski on wed 13 feb 08
I do not believe this myself. But it did happen.
I have kept notebooks forever--ok only for 58 years!--and of recent have
added
printouts of messages that matter.
This winter I am putting all lead-free recipes in my GlazeMaster (TM)
file....and found this message from St Alisa ; all fully-UC words added by
me.
From ClayArt February 20, 2001
" Glaze test for WoDo White, cone 6, oxidation
"Source: Original Dolomite White recipe from T. Martens, South Africa
"Tested on light light tan, mid range stoneware, fired to cone 6 oxidation.
"Recipe:
49 Neph.Sye.
25 Dolomite
6 Wollastonite
20 Ball Clay
'Resulted in a white, semi matt, waxy, covering glaze. Stable and very
smooth to the touch. The painted mix of cobalt, rutile and ball clay on to
of the glaze gave undefined edges, and a nice play of blue lines spotted
with the rutile. NO COBALT GREENS LIKE ON THE THE ORIGINAL DOLOMITE RECIPE
but may need bigger testing surface.
"The original recipe (ToDo White) called for
50 Neph. Sye.
5 Whiting.
It is also a good glaze but more off white in color and a softer matt
surface that is NOT scratch resistant.
"This light adjustment with Wollastonite, produced a more scratch resistant
surface, but not completely hard like a higher gloss glaze. I am personally
happy for this adjustment, as it gives me a replacement glaze for the Waxy
White that is not working for me at the time."
Having copied all this let me add that Hopper spoeaks of cobalt and rutile
mix for dark green. So I would think, Mr Rabbit,
that you have your work cut out for you....
Lili Krakowski
Be of good courage
Ron Roy on sun 17 feb 08
Alisa says it's stable? In what way?
Certainly not in terms of leaching - low silica and probably not fully
melted - very hard to get an alumina matte glaze that is durable - John has
never found one.
RR
>From ClayArt February 20, 2001
>
>" Glaze test for WoDo White, cone 6, oxidation
>
>
>"Source: Original Dolomite White recipe from T. Martens, South Africa
>
>"Tested on light light tan, mid range stoneware, fired to cone 6 oxidation.
>
>"Recipe:
>49 Neph.Sye.
>25 Dolomite
>6 Wollastonite
>20 Ball Clay
>
>'Resulted in a white, semi matt, waxy, covering glaze. Stable and very
>smooth to the touch. The painted mix of cobalt, rutile and ball clay on to
>of the glaze gave undefined edges, and a nice play of blue lines spotted
>with the rutile. NO COBALT GREENS LIKE ON THE THE ORIGINAL DOLOMITE RECIPE
>but may need bigger testing surface.
>
>"The original recipe (ToDo White) called for
>50 Neph. Sye.
>5 Whiting.
>It is also a good glaze but more off white in color and a softer matt
>surface that is NOT scratch resistant.
>
>"This light adjustment with Wollastonite, produced a more scratch resistant
>surface, but not completely hard like a higher gloss glaze. I am personally
>happy for this adjustment, as it gives me a replacement glaze for the Waxy
>White that is not working for me at the time."
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Alisa Clausen on tue 19 feb 08
I read this because I do not know what the Re. Harken all Rabbits means
and glad I did, because it told about something I said!
On Sun, 17 Feb 2008 20:41:43 -0500, Ron Roy wrote:
>Alisa says it's stable? In what way?
>
>Certainly not in terms of leaching - low silica and probably not fully
>melted - very hard to get an alumina matte glaze that is durable - John
has
>never found one.
>
Hi Inter.net
Funny how terms take on meanings after we get them sorted out and accepted
over the years. At the time I wrote this report, I was using stable as
a term that meant stiff, or not fluid, and covering.
When John and Ron wrote MC6G we in general accepted that word in regards
to glaze to mean within the limits of stability, in view of leaching.
So, stable in the way that it stays put! Still a lovely mat white glaze.
Most mats are softer on the surface and I do not use Wo Do white for
example dishes, and I have colored it with cobalt and tin for a lavender.
After this discussion about Cobalt greens, it was said that Magnesium is
neither required or ot excluded (source such as Dolomite) however Titania
is required. Source such as Rutile or just Titanium Diox.
I found greens however, on my WoDo white glaze where I just brushed a
Cobalt wash stripe.
Good to get updates on our current defintions.
Best regards from Alisa in Denmark
Alisa Clausen on tue 19 feb 08
On Sun, 17 Feb 2008 20:41:43 -0500, Ron Roy wrote:
>Alisa says it's stable? In what way?
>
>Certainly not in terms of leaching - low silica and probably not fully
>melted - very hard to get an alumina matte glaze that is durable - John
has
>never found one.
>
>RR
>
>
I read this post because I was wondering what Harken all Rabbits meant.
I am having trouble getting posts out, but if this is nr. 2, so it is.
At the time I made this test and posted it in 2001, I was using the term
Stable to describe not fluid.
After John and Ron published MC6G a couple of years later, we in general,
accepted the term stable to mean a glaze that falls within the limits of
their research. Durable and stable have become mainstreams in our glaze
vocabularly since their book to describe glazes that do not break down or
leach.
Since then, I have described glazed which do not move as stiff, no
movement or stay put.
Good to update our vocabularies once in a while.
As far as Cobalt greens, when this was discussed at the time, I noted that
it was said that Magnesium was neither required nor be excluded, but
Titania was required. I found however, greens in Cobalt washes over the
WoDo White.
Best regards from Alisa in Denmark
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