variegated iron
A surprise glaze found in a line blend.
From left to right, the glazes in the line blend are, Left end,
tsabar-celadon-PAl, middle tsabar-celadon-iron-8,
The 'middle' glaze tsabar-celadon-iron-8, isn't halfway, rather it is two
thirds from the righ end, iron_8_R_C10_13PSi,
The middle glaze is a mixture of two glazes, the first an ivory waxy matte
eggshell glaze with spattered markings,
Really, I'd seen some strange markings with one of these glazes the inlay,
the other the background. That tickled me,
The result is a crusty mixed dry and waxy matte glaze in a rainbow of iron
colors.
The design on the plate is created by adhering a mask and then applying the main
glaze. After drying, the entire pot is
Inside of bowl:
Outside of bowl:
Inside of bowl:
Outside of bowl:
150 deg F an hour to 250 deg F
400 deg F an hour to 1800 deg F
300 deg F an hour to 2050 deg F
120 deg F an hour to 2310 deg F with a hold of 20 minutes at 2310 deg F
300 deg F an hour to 1750 deg F then a half hour hold at 1750 deg F
300 deg F an hour to 1700 deg F then a Three hour hold at 1700 deg F
25 deg F an hour to 1650 deg F then a one hour hold at 1650 deg F
K2O 0.21
Al2O3 0.56
SiO2 2.77
molecular percent Silica 63.6%
Added:
0.5% Silicon Carbide for local reduction.
K2O 0.11
Al2O3 0.56
SiO2 3.12
molecular percent Silica 63%
K2O 0.18
Al2O3 .57
SiO2 2.92
molecular percent Silica 63.3%
right end
iron_8_R_C10_13PSi.
one third from the left end
tsabar-celadon-PAl. It is closer to the left end.
the second a full gloss
saturated iron aventurine glaze. The middle glaze, a mongrel, with two
unrelated parents.
With such a disparate provenance, one doesn't know
what to expect, part of why I tested it.
nudged me to explore.
coated in wax, then the mask is removed
and the open area filled in with a second glaze.
The Two end glazes
Left end: glaze tsabar-celadon-PAl
bowl is ~3 inches in diameter
Right end: glaze iron_8_R_10_13PSi
plate is ~8 inches in diameter
The middle glaze
glaze tsabar-celadon-iron-8
bowl is ~3 inches in diameter
oxidation firing to cone 10 in an electric kiln
Firing profiles
Up Fire profile
Down Fire Profile
Clay body is a grolleg porcelain from Tacoma Clay Art Center.
glaze compositions
Empirical Formula tsabar-celadon-PAl :
Na2O 0.07
CaO 0.65
MgO 0.01
ZnO 0.06
Fe2O3 0.01
Empirical Formula iron_8_R_C10_13PSi :
Na2O 0.45
Li2O 0.25
CaO 0.17
MgO 0.02
Fe2O3 0.28
Empirical Formula tsabar-celadon-iron-8 :
Na2O 0.19
Li2O 0.10
CaO 0.47
MgO 0.02
ZnO 0.04
Fe2O3 .11