Iron Green
The glaze, alk_alberta_Z3V, is half alberta slip. In an oxidation firing, if
applied sufficiently thickly,
bowl is ~ 4 inches in diameter.
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 1850 deg F then a 2 hr hold at 1850 deg F
300 deg F an hour to 1750 deg F then a 1 hr hold at 1750 deg F
300 deg F an hour to 1700 deg F then a 3 hr hold at 1700 deg F
25 deg F an hour to 1650 deg F then a one hour hold at 1650 deg F
K2O 0.16
Al2O3 0.72
SiO2 3.89
molecular percent Silica 68.4%
There is a trace amount of TiO2 in this glaze, likely from the alberta slip.
TiO2 is a common contaminant
it is a drab, sage green, with significant
pin-holing due to insufficient melt at cone 10, as seen on the
inside of the
bowl. The outside, with a thinner application, is mixed yellows and browns.
Image of the glaze alk_alberta_Z3V
inside
outside
oxidation firing to cone 10 in an electric kiln
Firing profile
Up Fire profile cone 10
Down Fire Profile cone 10
Clay body is a grolleg porcelain from Tacoma Clay Art Center.
glaze compositions
Empirical Formula alk_alberta_Z3V:
Na2O 0.38
CaO 0.30
MgO 0.16
Fe2O3 0.06
TiO2 0.01
Remarks
in clays and feldspars.