Des & Jan Howard on sat 4 mar 06
Ivor
Adding something like soda ash may stuff up the result.
Another possibility to assist in the melt is to ball mill the
ingredients for 24-36 hours, don't decant excess water until clear.
Arabia once made a flameproof body, the only glaze possible was the
fired body ball milled to micro-fine slip.
Des
Ivor and Olive Lewis wrote:
>Must make some of this stuff. I will fire at cone 8 and use Soda ash as a flux.
>
>
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Des & Jan Howard
Lue Pottery
LUE NSW 2850
Australia
Ph/Fax 02 6373 6419
http://www.luepottery.hwy.com.au
Ivor and Olive Lewis on mon 6 mar 06
Dear Des Howard=20
Realising that Calcium Oxide, derived from any of the compounds =
suggested by the text you found together with Silica, is not going to =
melt at any temperature attainable by a potter I suggested Sodium =
Carbonate as something that will melt in the 850-900 Deg C range and =
serve as a flux to initiate sintering=20
Without sintering or the intervention of a solid state reaction or the =
use of a really high temperature not much will happen. This may explain =
the " 100 hours". Even if the assumption is made that Copper Oxide, =
which does have a melting point within reach of a pottery kiln will act =
as a solvent it is necessary to postulate that it will dissolve Calcium =
oxide. Molten Copper Oxide and molten silicon dioxide are immiscible and =
do not appear to react to form an chemical compounds. Nor can I find =
evidence to support a reaction between Cu2O and CaO.
Your suggestion to ball mill the mix could be promising if it were done =
dry and the Sodium carbonate added later.
"Another possibility to assist in the melt is to ball mill the
ingredients for 24-36 hours, don't decant excess water until clear.
Arabia once made a flameproof body, the only glaze possible was the
fired body ball milled to micro-fine slip.
Des"
This seems logical, an offshoot of the Terra Sig process.
Such mind twisting problems we set for ourselves!
All he best,
Ivor.
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