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help with saggar

updated wed 15 nov 00


Stephani Stephenson on tue 14 nov 00

Jody wrote
just completed the second of my first two saggar
firings and couldn't have had more opposite results.
The first came out wonderfully--lots of colors and
shades. The second firing came out almost completely
black. The only differences between the 2 firings
were that during the second firing, the saggar had
several cracks, and I packed the sawdust very tightly
around the piece. I am thinking that possibly air got
into the saggar through the cracks and caused the
firing to turn the pot black. Does this make sense?

I think just the opposite happened, if I read your post correctly.
Sounds like to compensate for the cracks in the saggar, you packed
sawdust tightly.
The sawdust is the culprit. It likely prevented enough air i.e. oxygen.
from circulating in the saggar.
The sawdust would be responsible for the heavy reducing (carbon
monoxide rather than oxygen) atmosphere
and that would turn your pot black.
areas that are packed loosely, or packed with not combustible objects
like bisque shards will provide pockets where oxygen
can circulate in the saggar.
This will give you lighter areas and promote flashing and color
variation as well.
Every firing is likely to differ somewhat
Stephani Stephenson
Leucadia CA