Saturated Iron Glaze in different firings
cone 10 oxidation
Firing profiles
Down Fire profile 1 with a two hour hold at 1850 deg F
A two hour hold at 1850 deg F
A half hour hold at 1750 deg F
A three hour hold at 1700 deg F
slow downfire at 25 deg F an hour in the interval 1700 deg F to 1650 deg F
A half hour hold at 1650 deg F
Down Fire profile 2 without the hold at 1850 deg F
A half hour hold at 1750 deg F
A three hour hold at 1700 deg F
slow downfire at 25 deg F an hour in the interval 1700 deg F to 1650 deg F
A one hour hold at 1650 deg F
Clay body is a grolleg porcelain from Tacoma Clay Art Center.
In Previous Firings
Glazes were seen previously in a various firing in the same kiln.
Details of the glaze composition are found there.
The pots are mugs ~5 inches in high.
Several of these pots had a contrast wash over a leaf print in the leather
hard glaze.
In some cases the glaze flowed sufficiently that the origin
of the leaf is unrecognizable.
glaze satIron_ZG_0
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The mug on the left is fired with Downfire Protocol 1, with the additional 2
hour hold at 1850 deg F.
the mug on the right was fired with Downfire
Protocol 2.
I interpret the finer crystals in the first mug to result from the formation
of more crystal cluster during the long hold at the
higher temperature.
This inhibits the growth of large clusters.
more mugs with the second Downfire protocol
These glazes on vertical surfaces are similar to their
appearance on flat bowls.
Their high alkalinity does not
prevent their use on vertical surfaces.
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glazes satIron_ZG_H_5 and satIron_ZG_4
glaze satIron_ZG_H_5