AHarri9656 on fri 22 may 98
Dear Clayart Members,
For those of you who gave me info, Thanks....I really appreciate it. Now I
have another dilemma........can anyone give me some info on sources for Rice
Bran Ash (a.k.a Nuka or Rice Hush Ash), powdered Volcanic stone (like or
similiar to Hamada's Kaki glaze), and just plain old ash coming from different
organic matter? I know I can make my own ash. I could probably also make the
Rice Bran Ash if someone could tell me where I can get some of this material.
I also thought I could use the Volcanic rocks sold in stores for the backyard
gas grill. About this I wonder, is it safe? I assume these rocks have not
been treated, but I'm interested to know whether any of you ever tried this?
Any info would be greatly appreciated.......
Alex
GURUSHAKTI on sat 23 may 98
There is a product called "Clean Sweep" that you can buy at janotorial supply
stores. It's made of rice hull ash. They use it as a cleaning tool - spread on
dirty,oil floor and sweep up clean! :-)
Regards,
June
Plaznclay on sat 23 may 98
Alex,
Try to get a copy of Phil Rodgers "Ash Glazes." Good book. He talks about
using ash substitutes if you can't get the real thing.
Here is Phil's rice straw ash substitute:
Potash feldspar 9
Dolomite 3.5
Bone ash 2
Talc 13.5
China Clay 17.25
Quartz 55
Iron (FeO) 1.5
I haven't tried this myself but it is worth a try. Let me know how it goes,
if you test it.
Jenny D.
Dave Eitel on sat 23 may 98
..can anyone give me some info on sources for Rice
>Bran Ash (a.k.a Nuka or Rice Hush Ash), powdered Volcanic stone (like or
>similiar to Hamada's Kaki glaze), and just plain old ash coming from different
>organic matter? I know I can make my own ash. I could probably also make the
>Rice Bran Ash if someone could tell me where I can get some of this material.
>I also thought I could use the Volcanic rocks sold in stores for the backyard
>gas grill. About this I wonder, is it safe? I assume these rocks have not
>been treated, but I'm interested to know whether any of you ever tried this?
In his book "Ash Glazes" Phil Rogers gives this recipe for rice husk ash:
Ash 50
Feldspar 60
Quartz 40
He writes" Rice husk ash is almost pure silica, often 95% pure... Use this
[formula] as a starting point...It is a glaze high in silica and relies,
for its milky whiteness, on a surfeit of silica remaining unfluxed and
suspended in the glaze melt. It requires a high firing temperature of at
least 1280 C and preferably 1300 C."(p.23)
Later in the book (p.81) he refers to an analysis by Bernard Leach of "rice
straw" ash:
China clay 20
dolomite 3.5
talc 1.3
quartz 56.75
potasisium carb 2
bone ash 2
Iron oxide 2
There is also a chart at the back of the book which gives analyses of a
number of different ashes, including rice husk (p. 139) For rice husk it is:
SiO2--94.36
Al2 O3 --1.78
Fe2 O3--.61
Ca O--1.04
K2 O--1.35
Dave
Dave Eitel
Cedar Creek Pottery
Cedarburg, WI USA
http://www.cedarcreekpottery.com
John K. Dellow on sun 24 may 98
Plaznclay wrote:
> ----------------------------Original message----------------------------
> Alex,
>
> Try to get a copy of Phil Rodgers "Ash Glazes." Good book. He talks about
> using ash substitutes if you can't get the real thing.
>
> Here is Phil's rice straw ash substitute:
>
> Potash feldspar 9
> Dolomite 3.5
> Bone ash 2
> Talc 13.5
> China Clay 17.25
> Quartz 55
> Iron (FeO) 1.5
>
> I haven't tried this myself but it is worth a try. Let me know how it goes,
> if you test it.
>
> Jenny D.
Jenny which dolomite ?. English or synthetic, there is a diffrence in fired
result, if synthetic is subtituted for english in a glaze.
John (jacka) Dellow
Blue Mtns Pottery
Gold Coast Australia
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