Richard Burkett on sat 17 may 97
---------- Forwarded message ----------
Dear Sue,
re: your request for fake ash glazes here's one that we make called
BP26S Light green 'ash' glaze. The glaze is typically low in silica and
high in the alkaline earths - calcium and magnesia, and of the type that
has a shiny glassy melt within which satiny matt crystals develop.
Because it's used by electric kiln potters the light green colour is
given by copper carbonate. If to be used in a reduction firing one would
probably want to take out the copper and put in a few percent of iron
oxide.
BP26S Light green 'ash' glaze. Cone 8
Potash feldspar 40.0
China clay 20.0
Dolomite 18.0
Talc 8.0
Whiting 5.0
Zinc oxide 4.0
Quartz or flint 5.0
Copper carb. 1.0
Recipe for a synthetic wood ash.
Nepheline syenite 10
F3110 (a high soda frit) 8
Bone ash 6
Dolomite 20
Talc 5
Whiting 37
Zinc oxide 2
Bentonite 3
Soda ash 4
Titannium dioxide 2
Black iron oxide 3
The rationale behind this concoction is that it simulates a wood ash by
providing a glaze ingredient that's low in alumina & silica but high in
calcium with a combination of other fluxes.
Hope these are of some interest,
Best regards, Mike Bailey.
--
Mike Bailey,
Bath Potters' Supplies.
Tony Hansen on mon 19 may 97
Richard Burkett wrote:
> re: your request for fake ash glazes here's one that we make called
> BP26S Light green 'ash' glaze. The glaze is typically low in silica and
> high in the alkaline earths - calcium and magnesia, and of the type that
> has a shiny glassy melt within which satiny matt crystals develop.
Now that's an answer. Richard is giving us the 'mechanism' of the glaze.
He's telling us why it does what it does, not just throwing a recipe at
us.
=================================================================
Tony Hansen, IMC thansen@mlc.awinc.com
Richard Burkett on tue 20 may 97
Tony Hansen says:
>Richard Burkett wrote:
>> re: your request for fake ash glazes here's one that we make called
>> BP26S Light green 'ash' glaze. The glaze is typically low in silica and
>> high in the alkaline earths - calcium and magnesia, and of the type that
>> has a shiny glassy melt within which satiny matt crystals develop.
>
>Now that's an answer. Richard is giving us the 'mechanism' of the glaze.
>He's telling us why it does what it does, not just throwing a recipe at
>us.
>Tony Hansen, IMC thansen@mlc.awinc.com
Tony,
Read your mail more carefully! I would have said the same thing, thanks,
but the message about fake ash glazes was a forward from Mike Bailey of
Bath Potters' Supplies, who sent it to me by mistake.
This is the kind of knowledge that can be gained through having a database
of glazes to review, including a lot of those "textbook" glazes. Having a
number of recipes of the same type to study can really add to ones
perception of how glazes work, and what fluxes and other factors influence
color and surface development in glazes, and greatly aid in developing
ones one palette of glazes.
Richard Burkett - School of Art, SDSU, San Diego, CA 92182-4805
E-mail: richard.burkett@sdsu.edu <-> Voice mail: (619) 594-6201
Home Page: http://rohan.sdsu.edu/dept/rburkett/www/burkett.html
CeramicsWeb: http://apple.sdsu.edu/ceramicsweb/index.html
HyperGlaze@aol.com & http://members.aol.com/hyperglaze/
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