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the nature of reduction was several thoughts in a

updated tue 30 may 06


Ivor and Olive Lewis on mon 29 may 06


Dear David Beumee,

There is an interesting article in the recently published "Ceramics =
Technical", Issue No 22. Title "Ceramic Investigators". PP 81-86 from =
which I quote the student, Amanda Busby, who did the research....

" I found that near prefect combustion (11.5% CO2) produced the best =
result for copper red..... I learned from the FTIR Spectrophotometer =
that the ratio of CO2 to CO (Carbon Monoxide) was an indicator for =
Copper red. The FTIR indicated that a ratio of 355/1 CO2 to CO seemed =
good for Copper Red."=20

This seems like an open challenge to the Folk Lore of the Ceramic Arts

It would help me if you were able to summarise Pete Pinnell's findings. =
Can you please post them to clayart.

I maintain that, though the Oxyprobe may be a useful tool to get =
consistent firings, its readings tell us nothing about the gaseous =
nature of a kiln atomospheres. Mel's remarks about his high temperature =
firings where there is no attempt to induce reduction during heating =
(Did I understand that correctly Mel ?) but introduces carbon during =
the cooling cycle are important if there is positive indication of =
reduction transmutations.

Your remarks about the reluctance of people to change their entrenched =
views needs support. Antiquated ideas should be challenged with good =
research using the most modern tools available.

Thanks for being open about the topic.

Best regards,

Ivor Lewis.
South Australia.