Migrating disparate abutting glazes
The interface of adjacent glazes from divergent glaze families.
The matrix glaze is a high iron glaze, high in alkali metals and
alumina, the inlay glaze by contrast
Several closeups of the interaction region of the two glazes are shown and,
for context, a picture of the pot.
The background glaze is satIron_ZG_Ip7_5; the foreground design is
glazed with hankPaper_Z1R_2C_1.
The design is created by adhering a mask and then applying the main
glaze. After drying, the entire pot is coated in wax,
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 0.07
Al2O3 0.71
SiO2 3.13
molecular percent Silica 63%
K2O 0.12
Al2O3 0.42
SiO2 2.7
molecular percent Silica 63%
Added:
1% Cobalt Carbonate
.67% Copper Carbonate
The
matrix glaze is higher in alkali metals, silica and alumina, while the inlay
glaze is high in BaO and SrO.
The mask for the inlay is a series of linked ovoids, a large part of the area
within these ovoids is a mix of
The matrix glaze was excessively thickly applied, resulting in the visible
crawling. That heavy application, however,
is high in alkaline earths, lower in
alumina and contains titanium.
then the mask is removed
and the open area filled in with a second glaze.
Close up Images of the interaction region
Image of the piece
plate with glaze satIron_ZG_Ip7_5 and inlay hankPaper_Z1R_2C_1
plate is 10 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
Background glaze
Empirical Formula satIron_ZG_Ip7_5 :
Na2O 0.43
Li2O 0.20
CaO 0.13
MgO 0.17
Fe2O3 0.1
P2O5 0.04
Inlay Glaze
Empirical Formula hankPaper_Z1R_2C_1 :
Na2O 0.12
Li2O 0.05
CaO 0.14
MgO 0.02
BaO 0.31
SrO 0.24
TiO2 0.14
Remarks
Both these glazes are exceedingly fluid.
inlay glaze and matrix glaze.
increased the running together
and merging of the two glazes. This pair of glazes work wonderfully
together,
but require balancing the required thickness of the matrix
for the effects, yet avoiding crawling.