Dean on wed 15 aug 07
The best true green I've seen is :
Reitz Green ^6-10 ox. or red.
Nepheline syenite 70
Petalite 15
Whiting 5
Ball clay 8
Gerstley borate 2
Rutile 2
Cobalt carbonate 1
There's a porcelain teapot with this glaze on my
website:
www.lightwavepottery.com
I fire in oxidation at ^10 but that's the high end of
this glaze, it looks good at ^6 but starts to break
down at ^11. Dark when thin, lighter when thicker.
It's most often fired in reduction but I don't think
atmosphere makes much difference. It breaks to a nice
blue on some clays (WS-10 from Laguna) Darker clays
will darken it a bit. There's many examples around in
books and magazines. It's high in alumina and can
pinhole-lengthen your bisque if it does to do a
complete carbon burnout.
enjoy,
Dean
____________________________________________________________________________________
Boardwalk for $500? In 2007? Ha! Play Monopoly Here and Now (it's updated for today's economy) at Yahoo! Games.
http://get.games.yahoo.com/proddesc?gamekey=monopolyherenow
Ron Roy on thu 16 aug 07
Hi Dean,
What do you mean by break down? I assume it's a matt glaze because the
ratio is only 4.71 (a clay matt) - maybe its not so matt above cone 10?
The alumina in this glaze is way up there at .86 - the upper limits for a
cone 10 glaze are commonly 5.5 so I am thinking this is going to be very
hard to melt.
Have you ever tested this glaze with vinegar?
I like the idea that there is no chrome but is it stable?
RR
>The best true green I've seen is :
>
>Reitz Green ^6-10 ox. or red.
>
>Nepheline syenite 70
>Petalite 15
>Whiting 5
>Ball clay 8
>Gerstley borate 2
>Rutile 2
>Cobalt carbonate 1
>
>There's a porcelain teapot with this glaze on my
>website:
>www.lightwavepottery.com
>I fire in oxidation at ^10 but that's the high end of
>this glaze, it looks good at ^6 but starts to break
>down at ^11. Dark when thin, lighter when thicker.
>It's most often fired in reduction but I don't think
>atmosphere makes much difference. It breaks to a nice
>blue on some clays (WS-10 from Laguna) Darker clays
>will darken it a bit. There's many examples around in
>books and magazines. It's high in alumina and can
>pinhole-lengthen your bisque if it does to do a
>complete carbon burnout.
>enjoy,
>Dean
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
John Sankey on fri 17 aug 07
"The alumina in this glaze [Reitz Green] is way up there at .86 -
the upper limits for a cone 10 glaze are commonly 5.5 so I am
thinking this is going to be very hard to melt."
I assume Ron meant .55, not 5.5
Its expansion is also very high at 7.0; most stonewares are lower
than this - mine for example is 6.6, so I would think crazing is
probable except on high-expansion porcelains or if applied very thin.
--
(Add 'Byrd' to the subject line of your reply to get through my spam filter)
| |
|
