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^10 oxidation

updated sat 31 may 97


Malone & Dean McRaine on sat 26 apr 97

Aloha. This is in response to Peggy Heer's 'I'm back' posting.
I work in ^10 oxidation on porcelain (Dave's Porcelain from Laguna) and
would be glad to share recipes. I don't understand why reduction is so
favored. The colors and textures I get are bright, rich, textured and deep.
Many of the reduction glazes that I have tested are great in ox. I have
several that I use a lot, Cobalt Green, purple, tourquoise, peach blossom,
white, a no-recipe scrap black, aprocot-beige, blue crystal... What are you
interested in? I think ^10 ox is one of the best kept secrets in ceramics,
be careful, you may find yourself neglecting your long, nerve wracking
sometimes unreliable reduction firings in favor of throwing a few switches.
Here's one (from Hamer)to tittalate you that you can't do in reduction.

Rose Pink ^10 ox (best on porcelain)

48 Cornwall stone
14 EPK
5 Silica
28 Whiting
5 Tin
0.05 Chrome

You may vary the chrome from 0.01-0.1. this glaze is smooth and soft and
craze free on my clay body. It shows every ridge in your surface and drip in
your glazing so glaze technique is important. White when too thin. If anyone
else wants to contribute to this forum, please do.
With Aloha blessings,
Malone on sun 27 apr 97

I have been thinking of firing some pieces at ^10 oxidation and your post
came at a right time. Your generosity is appreciated and any glaze that
you are willing to share, I would love to have. When you say best on
porcelain, would the results be similar on a white stoneware clay (182)
which I get from Ohio ceramics. It is the closest clay to porcelain that
I know.

Nancy Rogers on mon 28 apr 97

Thank you for your recent post to Clay Art. It encouraged me greatly as I am
in the process of switching to cone 10 from come 6. I've been reading all
the posts about glazing and rarely find anything favorable about oxidation.
I'm excited at the prospect of your sharing your recipes for the following
oxidation glazes at your convenience: Cobalt Green, purple, tourquoise,
white, blue crystal.
Nancy the Cracked Potter in Hershey, PA

Malone & Dean McRaine on sun 11 may 97

Aloha Clayarteers:
A little White wine is all I need to loosen my lip and my grip on my
precious stock of ^10 Ox recipes. Actually, I've had a lot moire than that
and plan on finishing the bottle before this message is dfone so let me
I had a lot of replyse tio my post on ^10 Ox glazes but have been off line.
The gods have blessed me with a country home on the north shore of Kauai to
which I had to move very quickly. Moving a home and studio to a smaller
space is a load of work and I think there was a dimensional shift in ther to
boot. Regardless, I am ecstatic to live in such a beautifyul place. ( I
could correct the typos but it heightens the inebriated quality, don't you
I apologize, I digress. Here are some of the ^10 Oxidation glazes I have
had goo luck with over the yearss. I use Dave's porcelain from Laguna.

Amdreson Pearl
13 Gerstly Borate
8.7 Whiting
2.2 Zinc
59.5 Custar Spar
3.8 Ball Clay
7.6 tin
0.54 copper Carb
13 barium (Can substitute 9-13 Strontnium to make it food safe)

Nice light robin's egg blue gloss, stable, pretty, unusual, similar to peach
blossom but less texture.
Emmanuel Cooper's Blue Crystal #383
35 G-200 Spar (Custar works too)
10 Whiting
20 dolomite
30 flint
10 Rutile
5 bentonite
1.5 Cobalt Carb.

You better have some wine yerself befor youtry this one! Quite variable.
At its best a beautiful slate blue with small crystals (1/16") peppering
the surface (green centers w/ white halo). slightly fluid. Narrow firing
range, just Knock down ^10 and leave it at that, soak it slightly cooler. I
usually soak between 2050-2150 F ( I think my pyrometer is a little low).
Soak time is important. Longer soak and the crystals completely cover the
surface. I found a 1/2 hr soak was about right. beautiful no matter how you
fire it. I've sold a lot of this.
Cobalt Green (from CM)
2 Gerstly Borate
5 Whiting
70 Neph sy
15 Petalite
8 ball clay
1 cobalt carb
2 rutile
2 bentonite

Nice, rich, appealing. Unlike any green you've ever seen. Breaks white over
raised decoration. Viscosity is important as glaze varies with thickness.
Thick=bright green, medium=dark green, thin=grey-blue.
30.8 Custar spar
3.6 Gerstly Borate
16.2 Dolomite
3.6 Whiting
20.8 EPK
14.4 Silica
0.9 cobalt carb
0.45 Chrome Ox.

Bulletproof. Great at all temps and thicknesses. Very stable
Hawaiian Tan
33 Dolomite
33Custar spar
33 Ball clay (OM-4)

Simple, easy tan. Semi-matt.
Kelly Cowan's black
20 dolomite
42 Soda spar
18 EPK
20 Flint
1 bentonite
3.5 red iron oxide
3.5 chrome ox
3.5 manganese ox
3.5 cobalt carb

Stable semimatt black. You can reduce the cobalt and increase the other
metals to save some $$.
30 Custar Spar
15 Dolomite
20 Ball clay (OM-4)
20 Flint
15 Bone Ash
10 Iron ox

Nice iron red, stable.
Waxy White / Lavender
41 potash spar (custar, g-200)
17 Gerstley Borate
7 Dolomite
17 Talc
5 Ball Clay
20 Flint
1.5 bentonite
5 Zircopax
for lavender add
1 cobalt
to breakup surface a bit add
2 Lithium

Bulletproof. Smooth semimatt. White is good over colored slips. Lavender
is great, ranges from pinkish to almost blue, popular. All temps and
Good in reduction.
40 any spar
20 whiting
10 EPK
20 Flint
3 Zinc ox
7 Rutile
2 bentonite

Aprocot at ^9, the hotter it gets the more I like it. More pink and broken
surface. Good in a wood kiln in reduction, too.
Peach Blossom
41.7 Flint
27.6 Neph sy
17.1 Gerstley Borate
12.7 dolomite
0.3 copper carb
0.3 yellow ochre
0.3 tin ox
1.5 bentonite

Pretty light blue. Needs to be thickish, but will run a little, don't overfire.

Rich surface
Royal Blue
38.5 Custar Spar
16.0 Whiting
5.0 Strontnium
19.7 EPK
15.1 Silica
4.5 titanium
1.8 Cobalt carb
1.0 bentonite

Non- toxic version of barium matt blue. Stable, strong color.
Touch of Moon ( I never understood this name)
50 Neph sy
30 Whiting
20 EPK
1 cobalt carb
1 chrome ox

Dark semi-matt jade/marble green. Looks like stone.
Last but not least-
Scrap Black-ecologists special
Keep a wash bucket for all your throwaway and cleanup. All dumped glaze
tests at all temps from raku to high-fire, clay washed off your hands, glaze
wiped off the bottom of pots, leftover glazes and tests you didn't like, etc.
Let it settle a bit and drain off the water.
Keep doing this and consolidate until you have a bucketful.
You might want to screen it but if you have ash in it like I do, maybe not.
Dump a bunch of oxides in it till it is really black. Iron chromate is
cheap, use it first. Then more iron, some manganese, and about 1% cobalt.
Gotta have the cobalt or it won't be really black. Test it till it's really

That's it. Good luck.